Submission #524524

#	Time	Username	Problem	Language	Result	Execution time	Memory
524524		CSQ31	The Big Prize (IOI17_prize)	C++17	20 / 100	76 ms	328 KiB

prize

#include "prize.h"
#include <bits/stdc++.h>
using namespace std;
int num = 0;
#define sz(a) (int)(a.size());
int solve(int l,int r,int lf = 0,int rg = 0){
	//cout<<l<<" "<<r<<'\n';
	if(l > r)return -1;
	int mid = (l+r)/2;
	int i,j;
	int cl = 0,cr = 0;
	for(i=mid;i<=r;i++){
		vector<int>res = ask(i);
		if(!res[0] && !res[1])return i;
		else if(res[0] + res[1] == num){
			if(!(res[1]-rg)){ //nothing to find on right side
			  i = r;
			  break;
		    } 
			cl = res[0];
			cr = res[1];
			break;
		}
	}
	if(i == mid)j = i;
	else{
		for(j=mid;j>=l;j--){
			vector<int>res = ask(j);
			if(!res[0] && !res[1])return j;
			else if(res[0] + res[1] == num){
				if(!(res[0]-lf)){ //nothing to find on left side
				  j = l;
				  break;
				} 
				cr = res[1];
				break;
			}
		}
	}
	int c = solve(i+1,r,cl,rg);
	if(c != -1)return c;
	c = solve(l,j-1,lf,cr);
	return c;
}
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
int find_best(int n) {
	for(int i=0;i<10;i++){ //random until find dao biggest guy 
		int c = uniform_int_distribution<int>(0,n-1)(rng); 
		vector<int>res = ask(c);
		num = max(num,res[0]+res[1]);
	}
	//d&c to try all small guys since < #small guys < sqrt(n)
	int ans = solve(0,n-1);
	return ans;
}

• Subtask 1: 20 / 20
• Subtask 2: 0 / 80