import java.io.*; import java.util.*; import java.text.*; import java.math.*; import java.util.regex.*; public class Solution { public static void main(String[] args) { Scanner in = new Scanner(System.in); int flag=0,flag1=0; int n = in.nextInt(); for(int a0 = 0; a0 < n; a0++){ int x = in.nextInt(); int y = in.nextInt(); if(x>0 || x<0) flag=1; if(y>0 || y<0) flag1=1; } if(flag==0 || flag1==0) System.out.println("YES"); else System.out.println("NO"); } }