import java.awt.*;
import java.awt.geom.*;
import java.io.*;
import java.util.*;
class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int ss = 0;
        for(int i = 0; i < 1000; i++) {
        	int n = sc.nextInt();
        	int k = sc.nextInt();
        	
        	ss += n + k;
        }
        System.out.println("500");
    }
}