Binary Search

Program on Binary Search

#include<iostream.h>
#include<conio.h>

void main()
{       clrscr();
int n, i, a[30], x, first, last, middle;
cout<<"How many elements would you like to enter?:";
cin>>n;

for (i=0; i<n; i++)
{
cout<<"Enter number "<<(i+1)<<": ";
cin>>a[i];
}
cout<<"Enter the number that you want to search:";
cin>>x;
first = 0;
last = n-1;
middle = (first+last)/2;
while (first <= last)
{
   if(a[middle] < x)
   {
first = middle + 1;

   }
   else if(a[middle] == x)
   {
cout<<x<<" is found in the array at the location "<<middle+1<<"\n";
break;
   }
   else {
last = middle - 1;
   }
   middle = (first + last)/2;
}
if(first > last)
{
   cout<<x<<" is not found in the array";
}
getch();
}