题解 | #字符个数统计#

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

int countChar(char *s){
    int marked[128] = {0};
    int c = 0;
    int l = strlen(s);
    for (int i = 0; i < l; i++){
        if(s[i] >=0 && s[i] <=127 && marked[s[i]] == 0){
            c++;
            marked[s[i]] = 1;
        }
    }
    return c;
}

int main() {
    char s[502];
    scanf("%s", s);
    int c = countChar(s);
    printf("%d\n", c);
    return 0;
}