Log statistics (double pointer)

  This problem is a double pointer problem , Let's sort the likes by time , We set up i and j Respectively indicates that the current time period is less than k Hot post boundary , Each time the right boundary corresponds to id Zanga 1, If satisfied, praise equals k, Set as true, When the time period is greater than k When the current left boundary is represented id Praise and subtract 1, Enumerate , Until the end , What needs attention is the boundary problem , See the code for details ：

#include<cstdio>
#include<iostream>
#include<cstring>
#include<vector>
#include<algorithm>
#include<map>
#include<cmath>
#include<queue>
using namespace std;
const int N=1e5+10;
bool vis[N];
int n,d,k,cnt[N];
struct node{
	int ts,id;
}p[N];
bool cmp(node a,node b)
{
	return a.ts<b.ts;
}
int main()
{
	cin>>n>>d>>k;
	for(int i=1;i<=n;i++)
		scanf("%d%d",&p[i].ts,&p[i].id),p[i].id++;
	sort(p+1,p+n+1,cmp);
	cnt[p[0].id]++;
	for(int i=0,j=1;j<=n;i++)
	{
		while(p[j].ts-p[i].ts<d&&j<=n)
		{
			cnt[p[j].id]++;
			if(cnt[p[j].id]==k) vis[p[j].id]=true;
			j++;
		}
		cnt[p[i].id]--;
	}
	for(int i=1;i<=100001;i++)
		if(vis[i]) printf("%d\n",i-1);
	return 0;
}