#include<stdio.h>

void sushu(int n1,int n2){

int i,j;

int count=0;

for(i=n1;i<=n2;i++){

for(j=2;j<i;j++){

if(i%j==0){

count=1;

break;

}

   }

if(count==0)

printf("%d是素数\n",i);

count=0;

}

}

int main(){

int n1,n2;

scanf("%d %d",&n1,&n2);

sushu(n1,n2);

}