Submission #292897

#	Time	Username	Problem	Language	Result	Execution time	Memory
292897		Saboon	The Big Prize (IOI17_prize)	C++17	0 / 100	1 ms	384 KiB

prize

#include "prize.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

int Max = 0;

int solve(int l, int r, int cnt, int pre = 0, int suf = 0){
    if (cnt == r-l)
        return -1;
    for (int mid = (l+r)>>1; mid < r; mid++){
        vector<int> res = ask(mid);
        if (res[0]+res[1] == 0)
            return mid;
        if (res[0]+res[1] == Max){
            int ret = solve(l,mid,res[0]-pre, pre, res[1]+1);
            if (ret != -1)
                return ret;
            return solve(mid, r, res[1]-suf, res[0]+1, suf);
        }
    }
    for (int mid = (l+r)>>1-1; mid >= l; mid--){
        vector<int> res = ask(mid);
        if (res[0]+res[1] == 0)
            return mid;
        if (res[0]+res[1] == Max){
            int ret = solve(l,mid,res[0]-pre, pre, res[1]+1);
            if (ret != -1)
                return ret;
            return solve(mid, r, res[1]-suf, res[0]+1, suf);
        }
    }
    return -1;
}

int find_best(int n){
    if (n <= 50000){
        for(int i = 0; i < n; i++) {
            vector<int> res = ask(i);
            if(res[0] + res[1] == 0)
                return i;
        }
    }
    Max = n;
    for (int i = 0; i < 500; i++){
        vector<int> res = ask(i);
        Max = max(Max, res[0]+res[1]);
        if (res[0] + res[1])
            return i;
    }
    return solve(0, n, Max);
}

Compilation message (stderr)

prize.cpp: In function 'int solve(int, int, int, int, int)':
prize.cpp:22:28: warning: suggest parentheses around '-' inside '>>' [-Wparentheses]
   22 |     for (int mid = (l+r)>>1-1; mid >= l; mid--){
      |                           ~^~

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