Submission #434774

#	Time	Username	Problem	Language	Result	Execution time	Memory
434774		dutch	The Big Prize (IOI17_prize)	C++17	0 / 100	108 ms	200 KiB

prize

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

const int LIM = 480;
int ans = -1, val = 0;
vector<int> q;

void search(int l, int r, int lx, int rx){
	if(l > r || ans >= 0 || lx + rx == val) return;
	int m1 = (l + r) / 2, m2 = m1 + 1, x, y;
	q[0] = q[1] = 0;
	array<int, 2> c = {0, 0};
	while(((l<=m1) || (m2<=r))){
		if(y = (m1-l > r-m2)) x = m1--;
		else x = m2++;

		q = ask(x);
		if(q[0] + q[1] == 0) return void(ans = x);

		if(q[0] + q[1] < val) ++c[!y];
		else break;
	}

	search(l, m1, lx, rx + c[1]);
	search(m2, r, lx + c[0], rx);
}

int find_best(int n){
	for(int i=0; i<min(n, LIM); ++i){
		q = ask(i);
		val = max(val, q[0] + q[1]);
	}

	search(0, n-1, 0, 0);
	return ans;
}

Compilation message (stderr)

prize.cpp: In function 'void search(int, int, int, int)':
prize.cpp:15:8: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   15 |   if(y = (m1-l > r-m2)) x = m1--;
      |      ~~^~~~~~~~~~~~~~~

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