Submission #642073

#	Time	Username	Problem	Language	Result	Execution time	Memory
642073		piOOE	The Big Prize (IOI17_prize)	C++17	20 / 100	97 ms	2632 KiB

prize

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

using namespace std;
using ll = long long;

int find_best(int n) {
    int i = 0;
    int logn = __lg(n) + 2;
    map<int, vector<int>> mp;
    int Q = 0;
    auto  my_ask = [&](int i) {
        if (mp.count(i)) {
            return mp[i];
        } else {
            ++Q;
            if (Q > 10000) {
                assert(false);
            }
            mp[i] = ask(i);
            return mp[i];
        }
    };
    for (; i < n;) {
        auto a = my_ask(i);
        if (a[0] == 0 && a[1] == 0) {
            return i;
        } else {
            int j;
            if (a[0] + a[1] < 100) j = 10;
            else if (a[0] + a[1] < 50) j = 7;
            else j = 20;
            for (; j > -1; --j) {
                if (i + (1 << j) < n && my_ask(i + (1 << j)) == a) {
                    i += 1 << j;
                }
            }
            ++i;
        }
    }
    assert(false);
}

Compilation message (stderr)

prize.cpp: In function 'int find_best(int)':
prize.cpp:9:9: warning: unused variable 'logn' [-Wunused-variable]
    9 |     int logn = __lg(n) + 2;
      |         ^~~~

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