poj3190 Stall Reservations（贪心+STL）

https://vjudge.net/problem/POJ-3190

cin和scanf差这么多么。。tle和300ms

思路：先对结构体x升序y升序，再对优先队列重载<，按y升序。

　　然后依次入队，如果node[i].x<=q.top().y ans++， 否则出队，入队，使用出队的那个摊位。

 #include<iostream>
 #include<cstdio>
 #include<queue>
 #include<cstring>
 #include<algorithm>
 #include<cmath>
 #include<set>
 #define INF 0x3f3f3f3f
 typedef long long ll;
 using namespace std;
 struct Node{
     int x, y;
     int id;
     bool operator<(const Node &a)const{
         return y > a.y;
     }
 }node[];
 int n, maxm = -INF, b[];
 bool cmp(const Node a, const Node b)
 {
     if(a.x != b.x)
         return a.x<b.x;
     return a.y<b.y;
 }
 int main()
 {
     scanf("%d", &n);
     int ans = ;
     for(int i = ; i < n; i++){
         scanf("%d%d", &node[i].x, &node[i].y);
         node[i].id=i+;
     }
     sort(node, node+n, cmp);
     priority_queue<Node> q;
     q.push(node[]);
     b[node[].id] = ans;
     for(int i = ; i < n; i++){
         Node t = q.top();
         if(node[i].x <= t.y){
             q.push(node[i]);
             ans++;
             b[node[i].id] = ans;
             //maxm = max(maxm, ans);
         }
         else if(node[i].x > t.y){
             q.pop();
             q.push(node[i]);
             b[node[i].id] = b[t.id];
             //cout << b[t.id] << "t";
         }
     }
     printf("%d\n", ans);
     for(int i = ; i <= n; i++){
         printf("%d\n", b[i]);
     }

     return ;
 }