#include<stdio.h>
int main(){
    int month;
    scanf("%d", &month);
    
    switch(month) {
        case 1: case 3: case 5: case 7;
        case 8: case 10: case 12: 
        printf("31 days");
        break;
        
        case 4: case 6: case 9: case 11:
        printf("30 days");
        break;
        
        case 2:
        printf("28 days");
        break;
        
        default:
        printf("Invalid input");
    }
    return 0;
}