c programming using pointers

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EX NO: IMPLEMENTATION OF RECURSIVE ALGORITHM

DATE: USING POINTER

AIM:

To write a C-Program to implement a recursive algorithm using pointers ALGORITHM:

STEP 1: Start the program

STEP 2: Declare the variable, *no, factorial, sum, p, i, and the function fact(int p), sum(int p), fib(int p)

STEP 3: Read the value of no.

STEP 4: Call the function fact(*no), sum(*no)

STEP 5: Using a for loop call the function fib(int p) and display the Fibonacci series & also display factorial & summation.

STEP 6: Stop the program FUNCTION FIB (int p)

STEP 1: Check whether the value of n is equal to ‘0’ if so return ‘0’ STEP 2: Else check whether (p>=1 && p<=2), if so return the value ‘1’ STEP 3: Else return ( fib(p-1)+ fib(p-2))

FUNCTION FACT (int p)

STEP 1: Check whether (p==0), if so return ‘1’. STEP 2: Else return (p*fact(p-1))

FUNCTION SUM (int p)

STEP 1: Check whether p==0, if so return ‘0’ STEP 2: Else return (p+sum(p-1))

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PROGRAM:

#include<stdio.h> #include<conio.h> void main()

{

int i,p, *no,factorial,summ; int fact(int p);

int sum(int p); int fib(int p); clrscr();

printf("\n Enter The Number:"); scanf("%d",no);

printf("\n The Fibonnacci series: \n"); for(i=0;i<*no;i++)

printf("%d\n",fib(i)); factorial=fact(*no);

printf("\n The factorial of %d: %d\n", *no,factorial);

summ=sum(*no);printf("\nThe summation of %d: %d\n", *no,summ); getch(); } int fib(int p) { if(p==0) return(0); if(p>=1&&p<=2) return(1); else return(fib(p-1)+fib(p-2)); } int fact(int p) { if(p==0) return(1); else return(p*fact(p-1)); } int sum(int p) { if(p==0) return(0); else return(p+sum(p-1)); }

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OUTPUT:

Enter the Number: 5 The Fibonacci series: 0 1 1 2 3 The factorial of 5: 120 The summation of 5: 15

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RESULT:

Thus the C-Program was written to implement a recursive algorithm using pointers and the output was verified

(5)

`EX.NO: IMPLEMENTATION OF BUBBLE SORT DATE:

AIM: To write a C-Program to implement bubble sort using pointers and functions ALGORITHM:

STEP 1: Start the program STEP 2: Read the value of n

STEP 3: Set a for loop to read the elements of array for(i=0;i<n;i++)

STEP 4: Call the function bubblesort(a,n) STEP 5: Print the sorted array a

STEP 6: Stop the program

FUNCTION BUBBBLESORT (int *b[], int n) STEP 1: Declare the local variable.

STEP 2: Set a for loop

for(i=0;i<n;i++) STEP 3: Nest another for loop

for(j=1;j<n;j++) STEP 4: Check the condition

b[i]>b[j]

STEP 5: If so swap the two values using temporary variable t as t=a[i]

b[i]=b[j] b[j]=t

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PROGRAM: #include<stdio.h> #include<conio.h> void bubblesort(int*[],int); void main() { int i,n,a[100]; clrscr();

printf("\n Enter the number of elements:"); scanf("%d",&n);

printf("\n Enter the array elements"); for(i=0;i<n;i++)

scanf("%d",&a[i]);

printf("\nUNSORTED ARRAY ELEMENTS"); for(i=0;i<n;i++) printf("\t%d",a[i]); bubblesort(a,n); printf("\nSORTED ARRAY"); for(i=0;i<n;i++) printf("\t%d",*(a+i)); getch(); }

void bubblesort(int* b[],int n) { int i,j,t; for(i=0;i<n;i++) { for(j=i+1;j<n;j++) { if(b[i]>b[j]) { t=b[i]; b[i]=b[j]; b[j]=t; } } } }

(7)

OUTPUT:

Enter the number of elements:6 Enter the array elements 34 32

12 456 43 56

UNSORTED ARRAY ELEMENTS 34 32 12 456 43 56

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RESULT:

Thus the C-Program was written to implement bubble sort using pointers and functions and the output was verified successfully.

(9)

EX.NO: IMPLEMENTATION OF SELECTION SORT DATE:

AIM: To write a C-Program to implement selection sort using pointers and functions ALGORITHM:

STEP 4: Call the function sel(a,0,n-1) STEP 5: Print the sorted array a STEP 6: Stop the program

FUNCTION SEL (int *x, int start, int stop ) STEP 1: Declare the local variable.

STEP 2: Assign

begin =start and small=begin and check if start < stop

STEP 3: If so then set a for loop

for(i=begin+1;i<=stop;i++) STEP 4: Check the condition

x[i]<x[small]

STEP 6: If so then assign the value of i to small Small=i

STEP 7: Then swap the values of x[begin] and x[small] using temp temp=x[begin]

x[begin]=x[small] x[small]=temp

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PROGRAM:

#include<stdio.h> #include<conio.h> void sel(int *[],int,int); int main()

{

int a[100],i,n; clrscr();

printf("\nEnter The number Of elements:"); scanf("%d",&n);

printf("\nEnter the array elements one by one\n"); for(i=0;i<n;i++)

{

scanf("%d",&a[i]); }

printf("\nUNSORTED ARRAY ELEMENTS"); for(i=0;i<n;i++) printf("\t%d",a[i]); sel(a,0,n-1); printf("SORTED ARRAY:\n"); for(i=0;i<n;i++) { printf("\t %d",a[i]); } getch(); return(0); }

void sel(int *x[], int start, int stop) { int begin=start; int small=begin; int temp,i; if(start<stop) { for(i=begin+1;i<=stop;i++) { if(x[i]<x[small]) small=i; } temp=x[begin]; x[begin]=x[small]; x[small]=temp; sel(x,start+1,stop); } }

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OUTPUT:

Enter the number of elements:6

Enter the array elements one by one 23 45

89 98 09 65

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RESULT:

Thus the C-Program was written to implement selection sort using pointers and functions and the output was verified successfully.

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EX.NO: IMPLEMENTATION OF MERGE SORT DATE:

AIM: To write a C-Program to implement merge sort using divide and conquer strategy ALGORITHM:

STEP 4: Call the function split(a,0,n-1) STEP 5: Print the sorted array a

FUNCTION MERGE_SORT (int *a, int low, int high) STEP 1: Declare the local variable.

STEP 2: If low is less than high then assign the mean value of low and high to mid

mid =(low+high)/2

STEP 3: Call the function merge_sort(a,low,mid)

STEP 4: Call the another function merge_sort(a,mid+1,high) STEP 5: Call the function combine(a,low,mid,high)

FUNCTION SPLIT(int *c, int first, int last) STEP 1: Declare the local variables

STEP 2: Set the while loop till the condition i<=mid && j<=high is failed STEP 3: Check whether a[i]<a[j]

STEP 4: If so the assign the value of a[j] to temp[k] and increment j and k temp[k]=a[i]

j++ k++

STEP 5: Else assign a[j] to temp[k] and then increment j and k temp[k]=a[j] & j++ k++

STEP 6: Set another while loop till i is less than mid STEP 7: Assign the value of a[i] to temp[k]

temp[k]=a[i] & j++ k++

STEP 8: Set another while loop till j is greater than mid STEP 9: Assign the value of a[j] to temp[k]

temp[k]=a[j] j++ k++

STEP 10: Construct a for loop for k for(k=low; k<=high; k++) STEP 11: Assign the value of temp[k] to a[k]

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PROGRAM:

#include<stdio.h> #include<conio.h> void split(int *,int,int);

void merge(int *,int,int,int,int); int a[25],b[25];

void main() {

int i,n; clrscr();

printf("Enter the limit"); scanf("%d",&n);

printf("\n Enter the elements"); for(i=0;i<n;i++)

{

scanf("%d",&a[i]); }

split(a,0,n-1);

printf("\n The sorted list is:"); for(i=0;i<n;i++)

printf("\n %d",a[i]); getch();

}

void split(int *c,int first,int last) { int mid; if(first<last) { mid=(first+last)/2; split(c,first,mid); split(c,mid+1,last); merge(c,first,mid,mid+1,last); } }

void merge(int *a,int f1,int l1,int f2,intl2) { int i,j,k=0; i=f1; j=f2; while(i<=l1&&j<=l2) { if(a[i]<a[j]) b[k]=a[i++]; else b[k]=a[j++];

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k++; } while(i<=l1) b[k++]=a[i++]; while(j<=l2) i=f1; j=0; while(i<=l2&&j<k) a[i++]=b[j++] } OUTPUT:

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Enter the number of elements:6 Enter the array elements 23 45

89 98 09 65

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RESULT:

Thus the C-Program was written to implement merge sort using pointers and functions and the output was verified successfully.

EX.NO: IMPLEMENTATION OF BINARY SEARCH WITH RECURSION

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AIM: To write a C-Program to implement binary search using recursive functions ALGORITHM:

for(j=i+1;j<n;j++) STEP 6: Check the condition a[i]>a[j]

a[i]=a[j] a[j]=t

STEP 8: Else go back to step 6.

STEP 9: Set a for loop to print the value of array a For(i=0;i<n;i++)

STEP 10: Read the search key as k STEP 11: Assign low=0 and high=n-1

STEP 12: Call the function binsearch(a,k,low,high)

STEP 13: Check if ans is not equal to1 if so print the position b+i Else print that element is not found

FUNCTION BINARY SEARCH (int *x[ ], int x, int low, int high) STEP 1: Set a while loop till low is greater than high

STEP 2: Assign mean value of low and high to mid mid=(high+low)/2

STEP 3: Assign the value of x[mid] to p p=x[mid]

STEP 4: Check if x<p if so assign high=mid-1

STEP 5: Else check whether x>p if so then assign low=mid+1

STEP 6: Else check whether x= =p, if so return mid STEP 7: Else return -1

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#include<stdio.h> #include<conio.h> binarysearch(int *[],int,int,int); void main() { int i,j,k,t,low,high,n,a[50],ans; clrscr();

printf("\n enter the N:"); scanf("%d",&n);

printf("\n enter the array element one by one\n"); for(i=0;i<n;i++)

scanf("%d",&a[i]); printf("\n sorted array \n"); for(i=0;i<n;i++) for(j=i+1;j<n;j++) if(a[i]>a[j]) { t=a[i]; a[i]=a[j]; a[j]=t; } for(i=0;i<n;i++) printf("\t a[%d]=%d\n",i,a[i]); printf("\t enter the element to search:"); scanf("%d",&k);

low=0; high=n-1;

ans=binarysearch(a,k,low,high); if(ans!=-1)

printf("\nthe number %d is present in the list at location %d",k,ans); else

printf(" the number is not present in the list"); getch();

}

int binarysearch(int *a[],int x,int low,int high) { int mid,p; if(low>high) return-1; mid=(low+high)/2; p=a[mid]; if(x==p) return(mid); else if(x<p) return binarysearch(a,x,low,mid-1);

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else

return binarysearch(a,x,mid+1,high); }

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Enter the number of elements:6 Enter the array elements 23 45 89 98 09 65 SORTED ARRAY 09 23 45 65 89 98

Enter the element to search 23

The number 23 is present in the list at location 2 Enter the element to search 50

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RESULT:

Thus the C-Program was written to implement binary search using recursive functions and the output was verified successfully.

EX.NO: IMPLEMENTATION OF BINARY SEARCH WITHOUT RECURSION

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AIM: To write a C-Program to implement binary search using non-recursive functions ALGORITHM:

for(j=i+1;j<n;j++) STEP 6: Check the condition a[i]>a[j]

a[i]=a[j] a[j]=t

STEP 8: Else go back to step 6.

STEP 9: Set a for loop to print the value of array a for(i=0;i<n;i++)

STEP 10: Read the search key as k STEP 11: Assign low=0 and high=n-1

STEP 12: Call the function binsearch(a,k,low,high)

STEP 13: Check if ans is not equal to1 if so print the position b+i Else print that element is not found

FUNCTION BINARY SEARCH (int *a[ ], int x, int low, int high) STEP 1: Check if low>high if so return -1

STEP 2: Else assign mean value of low and high to mid mid=(high+low)/2

STEP 3: Assign the value of a[mid] to p p=a[mid]

STEP 4: Check if x= =p if so then return mid STEP 5: Else check whether x<p if so then return

binsearch(a,x,low,mid-1) STEP 6: Else return

binsearch(a,x,mid+1,high)

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#include<stdio.h> #include<conio.h> binarysearch(int *[],int,int); void main() { int i,j,n,a[10],t,k,b; clrscr();

printf(" ENTER THE NUMBER\n "); scanf("%d",&n);

printf("Enter array elements\n"); for(i=0;i<n;i++)

scanf("%d",&a[i]); printf("The sorted the array\n"); for(i=0;i<n;i++) for(j=i+1;j<n;j++) if(a[i]>a[j]) { t=a[i]; a[i]=a[j]; a[j]=t; } for(i=0;i<n;i++) printf("%d",a[i]);

printf("\nEnter the search element\n"); scanf("%d",&k);

b=binarysearch(&a,n,k); if(b!=-1)

printf("position:%d",b); else

printf("search element not found\n"); getch();

}

binarysearch(int *a[],int n,int k) { int mid,low,high,p; low=0; high=n-1; while(low<=high) { mid=(low+high)/2; p=a[mid]; if(p>k) high=mid-1; else if(p<k) low=mid+1; else if(k==p)

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return mid; }

return-1; }

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Enter the number of elements:6 Enter the array elements 23 45 89 98 09 65 SORTED ARRAY 09 23 45 65 89 98

Enter the element to search 23

The number 23 is present in the list at location 2 Enter the element to search 50

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RESULT:

Thus the C-Program was written to implement binary search without using recursive functions and the output was verified successfully.

EX.NO: IMPLEMENTATION OF QUICK SORT

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AIM: To write a C-Program to implement quick sort using pointers and functions ALGORITHM:

STEP 2: Assign the pointer array *a[100] as global, read the value of n STEP 3: Set a for loop to read the elements of array

for(i=0;i<n;i++) STEP 4: Call the function sort(0,n-1) STEP 5: Print the sorted array a STEP 6: Stop the program

FUNCTION SORT (int first, int last ) STEP 1: Declare the local variable. STEP 2: Check if first is less than last

first < last

STEP 3: If so then assign the following pivot=a[first]

i=first j=last

STEP 4: Assign a while loop till the condition i<j

STEP 5: Assign a while loop to increment i till a[i]<pivot and i< last

STEP 6: Assign a while loop to decrement j till a[j] > pivot and j > first

STEP 7: Check whether i is than j if so then swap the values of a[i] and a[j] temp=a[i]

a[j]=a[j] a[j]=temp

STEP 8: Then swap the values of a[j] and a[first] temp=a[j]

a[j]=a[first] a[first]=temp

STEP 9: Call another functions sort(first, j-1) and sort(j+1, last)

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#include<stdio.h> #include<conio.h> int *a[50],n,i; void sort(int,int); void main() { clrscr();

printf("Enter the No of Elements:"); scanf("%d",&n);

printf("Enter The Elements;"); for(i=0;i<n;i++)

scanf("%d",&a[i]);

printf("\nUNSORTED ARRAY ELEMENTS"); for(i=0;i<n;i++) printf("\t%d",a[i]); sort(0,n-1); printf("\nSORTED ARRAY"); for(i=0;i<n;i++) printf("%d",a[i]); getch(); }

void sort(int first,int last) { int *temp,*pivot,i,j; if(first<last) { pivot=a[first]; i=first; j=last; while(i<j) { while((a[i]<=pivot)&&(i<last)) i++; while((a[j]>=pivot)&&(j>first)) j--; if(i<j) { temp=a[i]; a[i]=a[j]; a[j]=temp; } } temp=a[first]; a[first]=a[j]; a[j]=temp; sort(first,j-1);

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sort(j+1,last); }

}

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89 98 09 65

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RESULT:

Thus the C-Program was written to implement quick sort using functions and pointers and the output was verified successfully.

EX.NO: IMPLEMENTATION OF INSERTION SORT

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AIM: To write a C-Program to implement insertion sort using pointers and functions ALGORITHM:

STEP 4: Call the function ins_sort(a,n) STEP 5: Print the sorted array a

FUNCTION INS_SORT (int *b[], int k ) STEP 1: Declare the local variable.

STEP 2: Set a for loop for p for(p=1;p<k;p++)

STEP 3: Assign the value of b[p] to temp temp=b[p]

STEP 4: Set a nested for loop for j

for(j=p;j>0&&b[j-1]>temp;j--)

STEP 5: Assign the value of b[j-1] to b[j] and temp to b[j] b[j]=b[j-1];

b[j]=temp;

STEP 6: Assign a while loop to decrement j till a[j] > pivot and j > first

STEP 7: Check whether i is than j if so then swap the values of a[i] and a[j] temp=a[i]

a[j]=a[j] a[j]=temp

STEP 8: Then swap the values of a[j] and a[first] temp=a[j]

a[j]=a[first] a[first]=temp

STEP 9: Call another functions sort(first, j-1) and sort(j+1, last)

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#include<stdio.h> #include<conio.h>

void ins_sort(int *a[], int n); void main()

{

int i,n,*a[50]; clrscr();

printf("Enter the number of Elements"); scanf("%d",&n);

printf("\nEnter the array elements \n"); for(i=0;i<n;i++) scanf("%d",&a[i]); printf("UNSORTED ARRAY:\n"); for(i=0;i<n;i++) printf("\t%d",a[i]); ins_sort(a,n); printf("SORTED ARRAY:\n"); for(i=0;i<n;i++) printf("\t%d",a[i]); getch(); }

void ins_sort(int *b[], int k) { int j,p,*temp; for(p=1;p<k;p++) { temp=b[p]; for(j=p;j>0&&b[j-1]>temp;j--) b[j]=b[j-1]; b[j]=temp; } OUTPUT:

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89 98 09 65

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RESULT:

Thus the C-Program was written to implement insertion sort using pointers and functions and the output was verified successfully.

EX.NO: IMPLEMENTATION OF 8 QUEEN PROBLEMS

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AIM: To write a C-Program to implement a 8 queen program using functions ALGORITHM:

STEP 1: Define the functions that are to be used STEP 2: Assign a constant value of 8 to QUEENNO STEP 3: Call the function placequeen(0,x)

STEP 4: Print the message “end” STEP 5: Stop the program

FUNCTION VOID PLACEQUEEN(int k, int *x) STEP 1: Declare local variables

STEP 2: Set a for loop for i for(i=0;i<8;i++)

STEP 3: Check for result of function canbeplaced(k,i,x) STEP 4: If it is 1 then assign the value of i to x[k]

x[k]=i;

STEP 5: Check if k is equal to 7 if show call the function showboard(x) STEP 6: Read the value of ch from the user

STEP 7: If the value is equal to n or N then exit

STEP 8: Check whether k is less than 7 if so then call the function placequeen(k+1,x)

FUNCTION INT CANBEPLACED(int k, int i, int *x) STEP 1: Declare the local variables

STEP 2: Set a for loop for j for(j=0;j<k;j++)

STEP 3: Check for the following condition

if((abs(j-k)==abs(x[j]-i)||(x[j]==i))) STEP 4: If its true return 0 else return 1

FUNCTION VOID SHOWBOARD(int *x) STEP 1: Declare the local variables

STEP 2: Set all the display style in printf function

STEP 3: Set a for loop for i to print 1,2,..8 vertically and horizontally for(i=0;i<8;i++)

STEP 4: Set another for loop for j and check whether j is equal to x[i] for(j=0;j<8;j++)

STEP 5: If so then print Q else print -PROGRAM:

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#include<stdio.h> #include<conio.h> #define QUEENNO 8 void placequeen(int,int*); int canbeplaced(int,int,int*); void showboard(int*); void main() { int x[QUEENNO],i; clrscr();

printf("the 8 queens problem"); placequeen(0,x);

printf("end"); getch(); }

void placequeen(int k,int *x) { int i,j; char ch; for(i=0;i<8;i++) { if(canbeplaced(k,i,x)) { x[k]=i; if(k==7) { showboard(x);

printf("want to see more?[n->stop, any-> continue]:"); scanf("%c",&ch); if(ch=='n' || ch=='N') exit(0); } if(k<7) placequeen(k+1,x); } } }

int canbeplaced(int k,int i,int *x) { int j; for(j=0;j<k;j++) { if((abs(j-k)==abs(x[j]-i))||(x[j]==i))) return 0; } return 1;

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} void showboard(int *x) { int i,j; printf("\n---\n"); printf(" "); for(i=0;i<8;i++) { printf("%d",(i+1)); printf(" "); } for(i=0;i<8;i++) { printf("\n\n%d",(i+1)); for(j=0;j<8;j++) { if(j==x[i]) printf("Q"); else printf("-"); printf(" "); } printf(""); } printf("\n---"); } OUTPUT:

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The 8 queens’ problem 1 2 3 4 5 6 7 8 1 Q 2 Q 3 Q 4 Q 5 – Q 6 Q 7 Q -8 - - - Q

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RESULT:

Thus the C-Program was written to implement an 8 queen program using functions and the output was verified successfully.

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DATE:

AIM: To write the C-Program to implement minimum spanning tree using structures, pointers and functions

ALGORITHM:

STEP 2: Assign MAX a constant value of 20

STEP 3: Declare a structure edge with structure variable *front

STEP 4: Define the functions and variables required in the program globally STEP 5: Call the function create_graph() inside the main function

STEP 6: Call the function make_tree() STEP 7: Set a for loop using i

for(i=1;i<=count;i++)

STEP 8: Print the values of tree[i].u and tree[i].v STEP 9: Stop the program

FUNCTION OF CREATE_GRAPH ( ) STEP 1: Declare the local variables STEP 2: Read the number of nodes n

STEP 3: Calculate the value of max_edge as max_edge=n*(n-1)/2

STEP 4: Set a for loop using i

for(i=0;i<=max_edge;i++) STEP 5: Read the values of origin and destin

STEP 6: Check whether origin and destin are equal to 0 STEP 7: If so exit the loop using break statement STEP 8: Read the weight of the current edge wt STEP 9: Check the following condition

if(origin>n||destin>n||origin<=0||destin <=0)

STEP 10: If any of the condition is true, print “invalid edge!” and decrement the value of i by 1 STEP 11: Else call the function insert_pque(origin,destin,wt)

STEP 12:Check whether i is less than n-1, if so then exit with an error message FUNCTION OF MAKE_TREE ( )

STEP 1: Declare the local variables

STEP 2: Initialize the variable tmp,node1,node2 STEP 3: Assign the values for node1, node2

STEP 4: Calculate and print the values of root_n1 and root_n2. STEP 5: If the two roots are not equal, call the function inset_tree STEP 6: Assign the value of root_n1 to father[root_n2]

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FUNCTION OF INSERT_TREE (int i, int j, int wt ) STEP 1: Declare the local variables

STEP 2: Increment the value of count

STEP 3: Assign values to tree[count].u, tree[count].v, tree[count].weight.

FUNCTION OF INSERT_PQUE (int i, int j, int wt ) STEP 1: Declare the local variables

STEP 2: Allocate the memory space of size, struct edge for tmp STEP 3: Assign values to tmp->u, tmp->v, tmp->weight.

STEP 4: Check for the following condition.

if(front==NULL||tmp->weight<front->weight)

STEP 5: If any of the conditions are true assign the value of front to tmp->link and assign tmp to front

STEP 6: else set a while loop and declare following q=q->link;

tmp->link=q->link; q->link=tmp; if(q->link==NULL) tmp->link=NULL;

FUNCTION OF STRUCT EDGE *DEL_PQUE( ) STEP 1: Declare the local variable

STEP 2: Assign the value of front to temp

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PROGRAM: #include<stdio.h> #include<conio.h> #define MAX 20 struct edge { int u; int v; int weight; struct edge *link; }

*front=NULL; int father[MAX]; struct edge tree[MAX]; int n;

int wt_tree=0; int count=0; void make_tree();

void insert_tree(int i, int j, int wt); void insert_pque(int i, int j, int wt); struct edge *del_pque();

void main() { int i; create_graph(); make_tree(); clrscr();

printf("edge to be included in spanning tree are:\n"); for(i=1;i<=count;i++)

{

printf("%d->",tree[i].u); printf("%d\n",tree[i].v); }

printf("weight of this minimum spanning tree is: %d\n",wt_tree); getch();

}

create_graph() {

int i,wt,max_edge,origin,destin; printf("enter no. of nodes"); scanf("%d",&n);

max_edge=n*(n-1)/2; for(i=0;i<=max_edge;i++)

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{

printf("enter edge %d(0 0 to quit):",i); scanf("%d%d",&origin,&destin); if((origin==0)&&(destin==0))

break;

printf("enter weight for this ecge"); scanf("%d",&wt); if(origin>n||destin>n||origin<=0||destin <=0) { printf("invalid edge!"); i--; } else insert_pque(origin,destin,wt); } if(i<n-1) {

printf("spanning tree is not possible"); exit(1); } return 0; } void make_tree() { struct edge *tmp; int node1,node2,root_n1,root_n2; while(count<n-1) { tmp=del_pque(); node1=tmp->u; node2=tmp->v; printf("n1=%d",node1); printf("n2=%d",node2); while(node1>0) { root_n1=node1; node1=father[node1]; } while(node2>0) { root_n2=node2; node2=father[node2]; } printf("rootn1=%d\n",root_n1); printf("rootn2=%d\n",root_n2); if(root_n1!=root_n2) {

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insert_tree(tmp->u,tmp->v,tmp->weight); wt_tree=wt_tree+tmp->weight; father[root_n2]=root_n1; } } }

void insert_tree(int i, int j, int wt) {

printf("This Edge inserted in the spanning tree\n"); count++;

tree[count].u=i; tree[count].v=j;

tree[count].weight=wt; }

void insert_pque(int i, int j, int wt) {

struct edge *tmp, *q;

tmp=(struct edge *)malloc(sizeof(struct edge)); tmp->u=i; tmp->v=j; tmp->weight=wt; if(front==NULL||tmp->weight<front->weight) { tmp->link=front; front=tmp; } else { q=front; while(q->link!=NULL&&q->link->weight<=tmp->weight) q=q->link; tmp->link=q->link; q->link=tmp; if(q->link==NULL) tmp->link=NULL; } }

struct edge *del_pque() {

struct edge *tmp; tmp=front;

printf("Edge Processed is %d->%d%d\n",tmp->u,tmp->v,tmp->weight); front=front->link;return tmp;

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OUTPUT:

NUMBER OF NODES: 3 Enter the Edge 1:2 2 Enter the weight: 1 Enter the Edge 2:2 3 Enter the weight: 2 Enter the Edge 3:2 1 Enter the weight: 5

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RESULT:

Thus the C-Program was written to implement minimum spanning tree using structures, pointers and functions and the output was verified successfully.