Submission

Score: 0

User: nemuchannnUwU

Problemset: ห้องสมุดเมือง 3M

Language: cpp

Time: 0.002 second

Submitted On: 2026-03-11 14:38:00

#include<bits/stdc++.h>
#define int long long
using namespace std;
main(){
	cin.tie(nullptr)->sync_with_stdio(0);
	int n,k; cin >> n;
	vector<int> x(n),y(n);
	int total=0;
	for (int i=0;i<n;i++){
		cin >> x[i] >> y[i];
		total+=(y[i]-x[i]);
	}
	int target=total/2;
	int l=0,r=20000000;
	int ans=0;
	while(l<=r){
		int mid=l+(r-l)/2;
		int cnt=0;
		for (int i=0;i<n;i++){
			if (mid<x[i]){
				cnt+=0;
			}else if(mid>=y[i]-1){
				cnt+=(y[i]-x[i]);
			}else{
				cnt+=mid-x[i]+1;
			}
		}
		if (cnt>=target){
			ans=mid;
			r=mid-1;
		}else l=mid+1;
	}
	cout << ans;
}