Submission #553947

#	Time	Username	Problem	Language	Result	Execution time	Memory
553947		timreizin	The Big Prize (IOI17_prize)	C++17	20 / 100	60 ms	5252 KiB

prize

#include "prize.h"
#include <random>

using namespace std;

int find_best(int n)
{
    random_device rd;
    mt19937 gen(rd());
    uniform_int_distribution<> dist(0, n - 1);
    vector<vector<int>> mem(n);
    int prev = -1;
    int sum = 0;
    for (int w = 0; w < min(200, n); ++w)
    {
        int j = dist(gen);
        if (mem[j].empty()) mem[j] = ask(j);
        vector<int> tmp = mem[j];
        if (tmp[0] + tmp[1] == 0) return j;
        sum = max(sum, tmp[0] + tmp[1]);
    }
    for (int i = 1;; ++i)
    {
        int l = 0, r = n - 1;
        //first with not max level
        while (l < r)
        {
            int m = (l + r) >> 1;
            if (mem[m].empty()) mem[m] = ask(m);
            if (mem[m][0] + mem[m][1] == 0) return m;
            if ((sum == mem[m][0] + mem[m][1] && mem[m][0] < i) || m <= prev) l = m + 1;
            else r = m;
        }
        prev = l;
        if (mem[prev].empty()) mem[prev] = ask(prev);
        if (mem[prev][0] + mem[prev][1] == 0) return prev;
    }
}
//1 2 5 26 677 - mins
//1 4 21 446 200000 - maxs

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