#include <stdio.h>

/* compute string length */
/* for illustration purposes only since there is a library function strlen */
int length1(char s[]) {
    int count = 0;
    while (s[count] != '\0') ++count;
    return count;
}

int main(void) {
    char s[100];
    printf("enter a line of input\n");
    fgets(s, sizeof(s), stdin);
    printf("length is %d\n", length1(s));
    return 0;
}