SER1


#include <stdio.h>

int main()
{
   int c, first, last, middle, n, search, array[100];

   scanf("%d",&n);


   for (c = 0; c < n; c++)
      scanf("%d",&array[c]);

   scanf("%d", &search);

   first = 0;
   last = n - 1;
   middle = (first+last)/2;

   while (first <= last) {
      if (array[middle] < search)
         first = middle + 1;   
      else if (array[middle] == search) {
         printf("%d found at location %d", 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);

   return 0; 
}