Submission #405332

#	Time	Username	Problem	Language	Result	Execution time	Memory
405332		dxz05	The Big Prize (IOI17_prize)	C++14	20 / 100	22 ms	12168 KiB

prize

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

using namespace std;

const int MAXN = 5e5 + 3e2;
typedef long long ll;

mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

int foo, hoo;

vector<int> asked_values[MAXN];

void ASK(int i){
    vector<int> res = (!asked_values[i].empty() ? asked_values[i] : ask(i));
    foo = res.front();
    hoo = res.back();
    asked_values[i] = res;
}

int find_best(int n) {
    int mn = 0;
    for (int i = 0; i < 1000; i++){
        int x = rng() % n + 1;
        ASK(x);
        if (foo + hoo == 0) return x;
        mn = min(mn, foo + hoo);
    }

	for (int i = 0; i < n; i++){
        int l = i, r = n - 1;
        int idx = n;
        while (l <= r){
            int m = (l + r) >> 1;
            ASK(m);
            if (foo + hoo == 0) return m;

            if (foo + hoo < mn) idx = m;

            if (foo){
                r = m - 1;
            } else l = m + 1;
        }
        i = idx + 1;
	}

	return 0;
}

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