贪心算法（题3）区间分组

#include<iostream>
#include<algorithm>//sort
#include<queue>//小根堆 
using namespace std;
const  int N=100010;
int n;
struct Range
{
	int l,r;
	bool operator < (const Range &W)const
	{
		return l<W.l;
	}
 }range[N];
 
int main()
{
	scanf("%d",&n);
	for (int i=0;i<n;i++)
	{
		int l,r; 
		scanf("%d%d",&l,&r);
		range[i]={l,r};
	}
	sort(range,range+n);
	
	priority_queue<int, vector<int>,greater<int> >heap;//写法 
	for(int i=0;i<n;i++)
	{
		auto r=range[i];
		if(heap.empty()||heap.top()>=r.l) heap.push(r.r);//为空或者不满足创新组 
		else
		{
			int t=heap.top();
			heap.pop();
			heap.push(r.r);
		}	
	 } 
	printf("%d\n",heap.size());
	return 0;
}