#include <stdio.h>
int rec(int n){
if(n == 1){
return 3;
}
else if(n == 2){
return 0;
}
else if(n == 3){
return 2;
}
else{
return rec(n-2) + rec(n-3);
}
}
int main(void){
for(int n = 1; n <= 50; n++){
}
return 0;
}
I2luY2x1ZGUgPHN0ZGlvLmg+CmludCByZWMoaW50IG4pewppZihuID09IDEpewpyZXR1cm4gMzsKfQplbHNlIGlmKG4gPT0gMil7CnJldHVybiAwOwp9CmVsc2UgaWYobiA9PSAzKXsKcmV0dXJuIDI7Cn0KZWxzZXsKcmV0dXJuIHJlYyhuLTIpICsgcmVjKG4tMyk7Cn0KfQppbnQgbWFpbih2b2lkKXsKZm9yKGludCBuID0gMTsgbiA8PSA1MDsgbisrKXsKcHJpbnRmKCIlZCAiLCByZWMobikpOwp9CnJldHVybiAwOwp9