3. Sort a given set of elements using the Merge sort method and determine the time requied to sort the elements. Repeat the experiment for different values of n, the number of elements in the list to be sorted and plot a graph of the time taken versus n.

#include<stdio.h>
#include<conio.h>
#include<time.h>
#define MAX 20
void mergesort(int a[],int low,int high);
void merge(int a[],int low,int mid,int high);
void main() { int n,i,a[MAX],
ch=1;
clock_t start,end; clrscr();
while(ch)
{
printf("\n \t enter the number of elements\n");
scanf("%d",&n); printf("\n \t enter the elements \n");
for(i=0;i<n;i++) scanf("%d",&a[i]);
start=clock();
mergesort(a,0,n-1); end=clock();
printf("\n the sorted array is \n"); for(i=0;i<n;i++)
printf("%d\n",a[i]);
printf("\n\ntime taken =%lf",(end-start)/CLK_TCK);
printf("\n \ndo u wish to continue(0/1)\n");
scanf("%d",&ch);
}
getch();
}
void mergesort(int a[],int low,int high)
{
int mid;
delay(100);
if(low<high)
{
mid=(low+high)/2;
mergesort(a,low,mid);
mergesort(a,mid+1,high);
merge(a,low,mid,high);
}
}
void merge(int a[],int low,int mid,int high)
{
int i,j,k,t[MAX];
i=low;
j=mid+1;
k=low;
while((i<=mid) && (j<=high))
if(a[i]<a[j])
t[k++]=a[i++];
else t[k++]=a[j++];
while(i<=mid)
t[k++]=a[i++];
while(j<=high)
t[k++]=a[j++];
for(i=low;i<=high;i++)
a[i]=t[i];
}