Submission #267807

#	Time	Username	Problem	Language	Result	Execution time	Memory
267807		PeppaPig	The Big Prize (IOI17_prize)	C++14	0 / 100	114 ms	11384 KiB

prize

#include "prize.h"
#include <bits/stdc++.h>

using namespace std;

vector<vector<int> > val;

vector<int> query(int i) {
	if(val[i][0] == -1) return val[i] = ask(i);
	return val[i];
}

bool valid(vector<int> vec) {
	return vec[0] + vec[1] == 0;
}

void solve(int l, int r, vector<int> &L, vector<int> &R, int &ans) {
	if(r - l <= 1 || ~ans) return;

	int mid = (l + r) >> 1;
	vector<int> M = query(mid);
	if(valid(M)) return void(ans = mid);

	if(L[0] + L[1] == R[0] + R[1] && M[0] + M[1] < L[0] + L[1] && L[0] == R[0] - 1)
		return;

	solve(l, mid, L, M, ans), solve(mid, r, M, R, ans);
}

int find_best(int n) {
	val = vector<vector<int> >(n, vector<int>(2, -1));

	vector<int> l = query(0), r = query(n - 1);
	if(valid(l)) return 0;
	if(valid(r)) return n - 1;

	int ans = -1;
	solve(0, n - 1, l, r, ans);

	return ans;
}

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