View Code of Problem 6

#include<bits/stdc++.h>
using namespace std;
int main () {
	int T,n,l[1000],r[1000],max, flag;
	cin>>T;
	while(T--) {
		cin>>n;
		max=0;
		for(int i=0; i<n; i++) {
			cin>>l[i]>>r[i];
			if(max<r[i]-l[i]) max=r[i]-l[i];//最大跳跃长度 
		}
		flag=1;
		for(int i=0; i<n-1; i++) {
			if(l[i]+max>l[i+1]) {
				flag=0;
				break;
			}
		}
		if(flag) cout<<"YES"<<endl;
		else cout<<"NO"<<endl;
	}
}