concat two strings and find their length.c

#include <stdio.h>

void main()
{
    char a[50], b[50], c[50];
    int i = 0;
    
    printf("Enter the first string: ");
    gets(a);
    
    printf("Enter the second string: ");
    gets(b);
    
    for(; a[i]!='\0';i++){
        c[i] = a[i];
    }
    for(int j=0; b[j]!='\0'; j++, i++){
        c[i] = b[j];
    }
    
    c[i] = '\0';
    
    printf("%s(length=%d)", c, i);
}