C program to find substring in a string

C program to find sub-string in a string

Output:

Enter the main string:
CodeRegister
Enter the substring to search:
Re
Substring Re found in CodeRegister

Implementation:

#include <stdio.h> #include <string.h> #include <stdlib.h> #define MAX 1000000 int main(void) { char str[MAX],sub[MAX]; const char *p; printf("Enter the main string:\n"); scanf("%s",str); printf("Enter the substring to search:\n"); scanf("%s",sub); p=strstr(str,sub); /* 0-based indexing */ if(p!=NULL) printf("Substring %s found at index %d in %s",sub,abs(abs(p)-abs(str)),str); else printf("Substring %s not found in %s",sub,str); return 0; }