pat1092 To Buy or Not to Buy

题意：Eva想要一串珠子，每个珠子有一个颜色，现在有一串珠子问Eva想要的珠子颜色在这串上是否都有，缺少则输出缺少多少个，多余则输出多余多少个。

思路：map计数即可。

代码

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <map>

using namespace std;

const int MAX_N = 1010;
char s1[MAX_N], s2[MAX_N];
map<char, int> mp;
int cnt = 0, res = 0;
bool flag = true;

int main() {
    // freopen("in.txt", "r", stdin);
    // freopen("out.txt", "w", stdout);
    scanf("%s %s", s1, s2);
    int len = strlen(s2);
    for (int i = 0; i < len; i++) {
        mp[s2[i]]++;
    }
    len = strlen(s1);
    for (int i = 0; i < len; i++) {
        mp[s1[i]]--;
    }
    for (auto it = mp.begin(); it != mp.end(); it++) {
        if (it->second > 0) {
            flag = false; res += it->second;
        } else if (it->second < 0) cnt += -(it->second);
    }
    if (flag) printf("Yes %d\n", cnt);
    else printf("No %d", res);
    return 0;
}