题解 | 删除字符串中出现次数最少的字符

//
// Created by gs on 2026/3/3.
//
#include <stdio.h>
#include <string.h>

int main() {
    char buf[21];
    int count[26];
    int len = 0;

    scanf("%s", buf);

    len = strlen(buf);
    memset(count, 0, sizeof (count));

    for(int i=0; i<len; i++){
        int n = buf[i] - 'a';
        count[n]++;
    }

    int min_count = 20;
    for(int i = 0; i<26; i++){
        if(count[i] > 0 && count[i] < min_count){
            min_count = count[i];
        }
    }

    for(int i = 0; i<26; i++){
        if(count[i] == min_count){
            for(int j = 0; j< len; j++){
                if(buf[j] == 'a' + i){
                    buf[j] = '0';
                }
            }
        }
    }

    for(int i = 0; i< len; ){
        if(buf[i] == '0'){
            for(int j = i; j< len; j++){
                buf[j] = buf[j+1];
            }
        }

        if(buf[i] != '0'){
            i++;
        }
    }

    printf("%s\r\n", buf);

    return 0;
}