#include<stdio.h>
    #include<string.h>
    void concat(char[], char[]);
    int main() {
    	char s1[50], s2[30];
    	printf("\nEnter String 1 :");
    	gets(s1);
    	printf("\nEnter String 2 :");
    	gets(s2);
    	concat(s1, s2);
    	printf("\nConcated string is :%s", s1);
    	return (0);
    }
    void concat(char s1[], char s2[]) {
    	int i, j;
    	i = strlen(s1);
    	for (j = 0; s2[j] != '\0'; i++, j++) {
    		s1[i] = s2[j];
    	}
    	s1[i] = '\0';
    }