cf-754 D Fedor and coupons（优先队列+区间贪心）

#include<iostream>
#include<stdio.h>
#include<stdlib.h>
#include<string>
#include<iomanip>
#include<algorithm>
#include<string.h>
#include<queue>
#include<cmath>
#include<stack>

using namespace std;
const int maxn=3e5+10;
const int inf=0x7f7f7f7f;
typedef long long ll;

int n,k;
struct node 
{
    int l,r;
    int idx;
    bool operator<(const node &n)const{
        return l<n.l;
    }
}a[maxn];
priority_queue<int, vector<int>, greater<int>> qq;
int st,ed;

int main()
{
    ios::sync_with_stdio(false);
    cin>>n>>k;
    for(int i=0; i<n; i++)
    {
        cin>>a[i].l>>a[i].r;
        a[i].idx=i+1;
    }
    sort(a,a+n);
    for(int i=0; i<n; i++)
    {
        if(qq.size()==k-1){
            int len=a[i].r-a[i].l+1;
            if(!qq.empty())
             len=min(len,qq.top()-a[i].l+1);
            if(len>ed-st){
                st=a[i].l;
                ed=a[i].l+len;
            }
        }
        qq.push(a[i].r);
        while(qq.size()>=k) qq.pop();
    }
    cout<<ed-st<<endl;
    int res=0;
    for(int i=0; i<n; i++)
    {
        if(res==k)
         break;
        if((a[i].l<=st&&a[i].r+1>=ed)||st==ed){
            cout<<a[i].idx<<" ";
            res++;
        }
    }
    cout<<endl;
    //system("pause");
    return 0;
}