题解 | #字符个数统计#

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

#define MAX 500

int char_No_duplicated(char c, char *s){
    for(int i = 0; i < strlen(s); i++){
        if(s[i] == c)
            return 0;
    }
    return 1;
}

int main(){

    char arr[MAX] = {0};
    fgets(arr, sizeof(arr), stdin);
    int len = strlen(arr);
    arr[len] = '\0';
    char new_arr[MAX] = {0};
    int new_len = 0;

    for(int i = 0; i < len; i++){
        if(char_No_duplicated(arr[i], new_arr)){
            new_arr[new_len++] = arr[i];
        }
    }
    printf("%d", new_len - 1);

    return 0;
}