#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>

int lengthOfLastWord(const char *s)
{
	if (!s || !*s) return 0;
	int len = strlen(s);
	int sum = 0;
	int i = len - 1;
	while (i >= 0 && !isalpha(s[i])) i--;
	while (isalpha(s[i])) {
		++sum;
		i--;
	}
	return sum;
}
int main(int argc, char** argv)
{
    const char* p;
    p = "hello world";
    printf("%s, %d\n", p, lengthOfLastWord(p)); 
    p = "a";
    printf("%s, %d\n", p, lengthOfLastWord(p)); 
    p = "              ";
    printf("%s, %d\n", p, lengthOfLastWord(p)); 
    
    if(argc>1){
        p = argv[1];
        printf("%s, %d\n", p, lengthOfLastWord(p)); 
    }
}