C :

#include "stdio.h"
#include "string.h"
#include <math.h>


int arr[30];


void main()
{
	char str[200];
	int i,length,max,min,z,sum;
	while (scanf("%s", &str) != EOF)
	{
		max = 0; min = 999999;
		for (i = 0; i <= 30; i++) arr[i] = 0;
		length = strlen(str);
		for (i = 0; i <= length; i++)
		{
			if ((str[i] >= 'a') && (str[i] <= 'z')) z = str[i] - 'a';
			else z = str[i] - 'A';
			arr[z]++;
			
		}
		for (i = 0; i <= 30; i++)
		{
			if (arr[i] > max) max = arr[i];
			if ((arr[i] < min)&&(arr[i]!=0))  min = arr[i];
		}
		sum = max - min;
		z = 0;
		for (i = 2; i < sum; i++)
		{
			if (sum%i == 0)
			{

				z = 1;
				break;
			}
		}
		if (( z== 0)&&(sum>1))	printf("Lucky Word\n%d\n", sum);
		else printf("No Answer\n0\n");
	}

}

C++ :

#include<stdio.h>
int judge(int a){
	if(a==1||a==0) return 0;
	for(int i=2;i<a;i++)
	if(a%i==0) return 0;
	return 1;
}
int main(){
	char a[101];
	while(scanf("%s",a)!=EOF){
		int b[26];
		for(int i=0;i<26;i++){
			b[i]=0;
		}
		int t=0,max=0,min=100;
		while(a[t]!=NULL){
			b[a[t]-97]++;
			t++;
		}
		for(int i=0;i<26;i++){
			if(max<b[i]) max=b[i];
			if(min>b[i]&&b[i]!=0) min=b[i];
		}
		if(judge(max-min)==1) {
			printf("Lucky Word\n");
			printf("%d\n",max-min);
		}
		else printf("No Answer\n0\n");
		
	}
	return 0;
}