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输出 2
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cpp
#include <iostream>
#include<algorithm>
using namespace std;
const int N =100010 ;
int n;
struct Range
{
int l,r;
bool operator <(const Range &W)const
{
return r<W.r;
}
}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);
int res=0, ed=-2e9;
for (int i=0;i<n;i++)
if(range[i].l>ed)
{
res++;
ed=range[i].r;
}
printf("%d\n",res);
return 0;
}
ed 上一个点的下标
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