UVALive - 7423

比赛的一个水题，英语不好，一开始把题意都错了， 后来改了下就对了，很简单的一个算是贪心的吧，代码如下 #include <iostream> #include <cstdio> #include <queue> #include <algorithm> #include <string> #include <cmath> using namespace std; struct people { int come, go; bool operator < (const people & p) { return come < p.come ||(come == p.come && go <p.go); } }person[300000+1]; int main() { int m, n; while(scanf("%d%d", &m, &n) != EOF) { priority_queue< int, vector <int>, greater<int> >q; int sum = 0, lock = 0; int come, go; for(int i = 0; i < m; i++) { scanf("%d%d", &person[i].come, &person[i].go); } sort(person, person + m); for(int i = 0;i < m; i++) { come = person[i].come; go = person[i].go; if(!q.empty() && come >= q.top() && come <= q.top() + n ) { q.pop(); lock++; } else if(!q.empty() && come > q.top() + n ) { while(come > q.top() + n && q.size() > 0) q.pop(); if(q.size() != 0) { q.pop(); lock++; } } q.push(come + go); } cout << lock << endl; } return 0; }