P1125 [NOIP2008 提高组] 笨小猴

题目传送门

#include <bits/stdc++.h>

using namespace std;
const int N = 30;
const int INF = 0x3f3f3f3f;
int Max, Min = INF;
int b[N];   //计数数组

bool IsPrime(int n) {
    if (n < 2) return false;
    for (int i = 2; i <= n / i; i++)
        if (n % i == 0) return false;
    return true;
}

int main() {
    string s;
    cin >> s;
    //计数 s[i] - 'a':映射坐标
    for (int i = 0; i < s.size(); i++) b[s[i] - 'a']++;
    //扫描一遍计数数组，统计最小值与最大值,注意判断一下0个的问题
    for (int i = 0; i < 26; i++) {
        Max = max(Max, b[i]);
        if (b[i] > 0) Min = min(Min, b[i]);
    }
    if (IsPrime(Max - Min)) printf("Lucky Word\n%d", Max - Min);
    else printf("No Answer\n%d", 0);
    return 0;
}