#include <stdio.h>
int main(void) {
int a[32],n,i,count,x,j;
i=0;
a[0]=2;
a[1]=-1;
x=0;
for(n=2;n<=32;n++){
a[n]=-a[n-1]+a[n-2]+2;}
for(j=0;j<=32;j++){
count=0;
if(a[j]>=2){
for(i=2;i<a[j];i++){
if(a[j]%i==0){
count++;}}
if(count==0){
x++;
}}}
return 0;
}
I2luY2x1ZGUgPHN0ZGlvLmg+CgppbnQgbWFpbih2b2lkKSB7CglpbnQgYVszMl0sbixpLGNvdW50LHgsajsKCWk9MDsKCWFbMF09MjsKCWFbMV09LTE7Cgl4PTA7CgkJZm9yKG49MjtuPD0zMjtuKyspewoJYVtuXT0tYVtuLTFdK2Fbbi0yXSsyO30KCWZvcihqPTA7ajw9MzI7aisrKXsKCQljb3VudD0wOwoJICAgaWYoYVtqXT49Mil7Cglmb3IoaT0yO2k8YVtqXTtpKyspewoJCQoJCWlmKGFbal0laT09MCl7CgkJCWNvdW50Kys7fX0KCQkJaWYoY291bnQ9PTApewoJCQkJeCsrOwoJfX19CglwcmludGYoIiVkIix4KTsKCXJldHVybiAwOwp9Cg==