题解 | #删除字符串中出现次数最少的字符#

#include <string.h>

int main(void) {
    char str[21];
    int index[21] = {0};
    int hash[21] = {0};

    scanf("%s", str);

    int length = (int) strlen(str);

    for (int i = 0; i < length; ++i) {
        index[i] = 1;
        for (int j = 0; j < length; ++j) {
            if (i == j)
                continue;
            else {
                if (str[i] == str[j])
                    index[i]++;
                else
                    continue;
            }
        }
    }
    for (int i = 0; i < length; ++i) {
        if (index[i] == 1)
            continue;
        else {
            for (int j = 0; j < length; ++j) {
                if (i == j)
                    continue;
                else {
                    if (index[i] > index[j]) {
                        hash[i] = 1;
                        break;
                    }
                }
            }
        }

    }

    for (int k = 0; k < length; ++k) {
        if (hash[k] == 1)
            printf("%c", str[k]);
        else
            continue;
    }
    return 0;
}