c
#include <stdio.h>
int main() {
    int N;
    scanf("%d", &N);
    if(N<=10)
        printf("%d", 6*N);
    else if(10<N && N<=20)
        printf("%d", 60+2*(N-10));
    else if(20<N && N<=40)
        printf("%d", 80+1*(N-20));
    else
        printf("100");
    return 0;
}