Submission #619252

#	Time	Username	Problem	Language	Result	Execution time	Memory
619252		SlavicG	The Big Prize (IOI17_prize)	C++17	20 / 100	71 ms	1384 KiB

prize

#include "prize.h"
#include "bits/stdc++.h"
using namespace std;

map<int, vector<int>> mp;
int ans = -1;
vector<int> query(int i) {
    if(mp.count(i)) return mp[i];
    vector<int> paiu = ask(i);
    mp[i] = paiu;
    if(paiu[0] + paiu[1] == 0) ans = i;
    return paiu;
}

void rec(int l, int r) {
    if(ans != -1) return;
    if(l >= r) return;
    int mid = l + r >> 1;

    if(query(mid)[0] + query(mid)[1] == 0) {
        ans = mid;
        return;
    }
    if(query(mid)[0] > query(l)[0] || query(mid)[1] < query(l)[1]) {
        if(ans != -1) return;
        rec(l, mid);
    }
    if(ans != -1) return;
    query(mid + 1);
    rec(mid + 1, r);
}

int find_best(int n) {
    ans = -1;
    mp.clear();
    rec(0, n - 1);
    return ans;
}

Compilation message (stderr)

prize.cpp: In function 'void rec(int, int)':
prize.cpp:18:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   18 |     int mid = l + r >> 1;
      |               ~~^~~

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