codeforces 1304C - Air Conditioner （贪心）

题目链接：https://codeforces.com/problemset/status?my=on

按时间排序，集合取交集

#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
#include<cmath>
#include<stack>
#include<queue>
using namespace std;
typedef long long ll;

const int maxn = 200;

int q,n,m;

struct P{
	int t,l,r;
}p[maxn]; 

bool cmp(P a,P b){ return a.t < b.t; }

ll read(){ ll s=0,f=1; char ch=getchar(); while(ch<'0' || ch>'9'){ if(ch=='-') f=-1; ch=getchar(); } while(ch>='0' && ch<='9'){ s=s*10+ch-'0'; ch=getchar(); } return s*f; }

int main(){
	q = read();
	while(q--){
		n = read(), m = read();
		int low = m, high = m;
		
		for(int i=1;i<=n;++i){ p[i].t = read(), p[i].l = read(), p[i].r = read(); }
		
		sort(p+1,p+1+n,cmp);
		
		int f = 0;
		for(int i=1;i<=n;++i){
			low -= p[i].t - p[i-1].t, high += p[i].t - p[i-1].t;
			if(low > p[i].r || high < p[i].l){
				printf("NO\n");
				f = 1;
				break;
			}
			low = max(low, p[i].l); high = min(high, p[i].r);
		}
		if(!f) printf("YES\n");
	}
	return 0;
}