C program for Binary Search.

#include<stdio.h>
#include<conio.h>
void main()
{
 clrscr();
 int n, i, arr[50], search, first, last, middle;
 printf("Enter total number of elements :");
 scanf("%d",&n);
 printf("Enter %d number :", n);
 for (i=0; i<n; i++)
 {
  scanf("%d",&arr[i]);
 }
 printf("Enter a number to find :");
 scanf("%d", &search);
 first = 0;
 last = n-1;
 middle = (first+last)/2;
 while (first <= last)
 {
  if(arr[middle] < search)
  {
   first = middle + 1;

  }
  else if(arr[middle] == search)
  {
   printf("%d found at location %d\n", search, middle+1);
   break;
  }
  else
  {
    last = middle - 1;
  }
  middle = (first + last)/2;
 }
 if(first > last)
 {
  printf("Not found! %d is not present in the list.",search);
 }
 getch();
}