洛谷 P1125 [NOIP2008 提高组] 笨小猴 题解 字符串 C/C++

//P1125 [NOIP2008 提高组] 笨小猴
//#define LOCAL
#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <cctype>
#define inf 0x3f3f3f3f
#define eps 1e-6
using namespace std;
#define clr(x) memset(x,0,sizeof((x)))
const int maxn = 5e4+1;//2e6+1
#define MAX(a,b,c) ((a)>(b)?((a)>(c)?(a):(c)):((b)>(c)?(b):(c)))
#define _max(a,b) ((a) > (b) ? (a) : (b))
#define _min(a,b) ((a) < (b) ? (a) : (b))
#define _for(a,b,c) for(int a = b;a<c;a++)
int readchar() {
    
    
	int ch;
	for(;;) {
    
    
		ch = getchar();
		if(ch!='\n'&&ch!='\r')return ch;
	}
}
int isPrime(int x) {
    
    
	if(x==0||x==1)return 0;
	for(int i = 2;i<=sqrt(x);i++) {
    
    
		if(x%i==0)return 0;
	}
	return 1;
}
int main() {
    
    
#ifdef LOCAL 
	freopen("data.in","r",stdin);
	freopen("data.out","w",stdout);
#endif
	int ch;
	int a[26+1];//26个英文字母
	clr(a);
	while((ch = readchar())!=EOF) {
    
    
		a[ch-'a']++;
	}
	int mx = -inf,mi = inf;
	for(int i = 0;i<26;i++) {
    
    
		if(a[i]) {
    
    
			mx = _max(mx,a[i]);
			mi = _min(mi,a[i]);
		}
		
	}
	if(isPrime(mx-mi)) {
    
    
		cout<<"Lucky Word"<<endl<<mx-mi;
	}
	else cout<<"No Answer"<<endl<<0;
	
	return 0;
}