Meeting rooms

//Meeting rooms

import java.io.*;
import java.util.*;

class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int T = Integer.parseInt(br.readLine().trim());

        while(T-- > 0) {
            int n = Integer.parseInt(br.readLine().trim());
            int[][] arr = new int[n][2];

            for(int i = 0; i < n; i++) {
                String temp[] = br.readLine().trim().split(" ");
                arr[i][0] = Integer.parseInt(temp[0]);
                String x = temp[1];
                arr[i][1] = Integer.parseInt(x);
            }

            Solution obj = new Solution();
            boolean ans = obj.canAttend(arr);

            if(ans) {
                System.out.println("true");
            }
            else {
                System.out.println("false");
            }
        }
    }
}

class Solution {
    static boolean canAttend(int[][] arr) {
        int n = arr.length;
        Arrays.sort(arr, (a, b) -> Integer.compare(a[0], b[0]));
        
        for(int i = 0; i < n - 1; i++) {
            if (arr[i][1] > arr[i + 1][0]) {
                return false;
            }
        }
        
        return true;
    }
}