Write a program to search a character in a string using binary search

Write a program to search a character in a string using binary search.

1. #include <stdio.h>
2. #include <string.h>
3.  
4. void main()
5. {
6.     int i, n, start, end, mid;
7.     char str[100][100], key[40];
8.    
9.     printf("Please enter the number of string to be stored : ");
10.     scanf("%d",&n);
11.    
12.     printf("Enter the string in ascending order\n");
13.    
14.     for(i=0; i<=n-1; i++) {
15.         scanf("%s", &str[i]);
16.     }
17.    
18.     printf("Enter the string to be searched : ");
19.     scanf("%s", &key);
20.    
21.     start = 0;
22.     end = n-1;
23.     while(start <= end) {
24.         mid = (start+end)/2;
25.         if (strcmp(key, str[mid])==0)
26.             {
27.                 printf("key found at the position %d\n", mid+1);
28.                 exit(0);
29.             }
30.         else if
31.             (strcmp(key, str[mid])>0)
32.             {
33.                 end = end;
34.                 start = mid+1;
35.             }
36.            
37.         else {
38.                 start=start;
39.                 end = mid-1;
40.             }
41.     }
42.     printf("Failed\n");
43.  }