#include <stdio.h>
#include <vector>
#include <algorithm>
#include <stack>

using namespace std;

int main(){
	int w,sum;

	while(true){
		scanf("%d",&w);
		if(w == -1)break;

		sum = 1150;

		if(w > 10){
			sum += 125*(min(10,w-10));
		}

		if(w > 20){
			sum += 140*(min(10,w-20));
		}

		if(w > 30){
			sum += 160*(w-30);
		}

		printf("%d\n",4280-sum);

	}

    return 0;
}