poj 3190

要用优先队列去维护结束的时间

代码如下

#include<cstdio>#include<iostream>#include<cstring>#include<algorithm>#include<queue>using namespace std;const int maxn=50005;int used[maxn];struct Node{int pos,l,r;bool operator <(const Node &a) const{return r>a.r||(r==a.r&&l>a.l);}}a[maxn];priority_queue<Node> q; bool cmp(Node a,Node b){if(a.l==b.l) return a.r<b.r;return  a.l<b.l;}int main(){int n;scanf("%d",&n);for(int i=0;i<n;i++){scanf("%d%d",&a[i].l,&a[i].r);a[i].pos=i;}int ans=1;sort(a,a+n,cmp);while(!q.empty()) q.pop();q.push(a[0]);used[a[0].pos]=1;for(int i=1;i<n;i++){if(!q.empty()&&q.top().r<a[i].l){used[a[i].pos]=used[q.top().pos];q.pop();}else{ans++;used[a[i].pos]=ans;}q.push(a[i]);}printf("%d\n",ans);for(int i=0;i<n;i++)printf("%d\n",used[i]);return 0;}