为什么是80分？#2 #4

#include<iostream>
#include<cstring>
using namespace std;
int pn(int x)
{
	for(int i=2;i*i<=x;i++)
	if(x%i==0)return 0;
	return 1;
}
int main(void)
{
	int max=1,min=100,leter[26]={0};
	char a[101];
	cin>>a;
	for(int i=1;i<=strlen(a);i++)
	{
		if(a[i]=='a')leter[0]++;
		if(a[i]=='b')leter[1]++;
		if(a[i]=='c')leter[2]++;
		if(a[i]=='d')leter[3]++;
		if(a[i]=='e')leter[4]++;
		if(a[i]=='f')leter[5]++;
		if(a[i]=='g')leter[6]++;
		if(a[i]=='h')leter[7]++;
		if(a[i]=='i')leter[8]++;
		if(a[i]=='j')leter[9]++;
		if(a[i]=='k')leter[10]++;
		if(a[i]=='l')leter[11]++;
		if(a[i]=='m')leter[12]++;
		if(a[i]=='n')leter[13]++;
		if(a[i]=='o')leter[14]++;
		if(a[i]=='p')leter[15]++;
		if(a[i]=='q')leter[16]++;
		if(a[i]=='r')leter[17]++;
		if(a[i]=='s')leter[18]++;
		if(a[i]=='t')leter[19]++;
		if(a[i]=='u')leter[20]++;
		if(a[i]=='v')leter[21]++;
		if(a[i]=='w')leter[22]++;
		if(a[i]=='x')leter[23]++;
		if(a[i]=='y')leter[24]++;
		if(a[i]=='z')leter[25]++;
	}
	for(int i=0;i<26;i++)
	{
		if(leter[i]>max)max=leter[i];
		if(leter[i]<min&&leter[i]>0)min=leter[i];
	}
	if(max-min==0||max-min==1)
	{
		cout<<"No Answer\n"<<0;
		return 0;
	}
	if(pn(max-min)==1)cout<<"Lucky Word\n"<<max-min;
	else cout<<"No Answer\n"<<0; 
	return 0;
}