#include <stdio.h>
int main(){
    int month;
    scanf("%d",&month);
    if(month==1||month==3||month==5||month==7||month==8||month==10||month==12){
        printf("31 days\n");
    }else if(month==4||month==6||month==9||month==11){
        printf("30 days\n;")
    }else if(month==2){
        print("28 days\n");
    }else{
        print("Invalid input\n");
    }
    return 0;
}