Submission #434783

#	Time	Username	Problem	Language	Result	Execution time	Memory
434783		dutch	커다란 상품 (IOI17_prize)	C++17	20 / 100	69 ms	328 KiB

prize

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

const int LIM = 480;
int ans, val;
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, cnt = -1;
	q[0] = q[1] = 0;
	while(q[0] + q[1] < val){
		if((y = m1-l > r-m2)) x = m1--;
		else x = m2++;
 
		q = ask(x);
		if(q[0] + q[1] == 0) return void(ans = x);
		++cnt;
	}

	if(y){
		search(l, m1, lx, q[1]);
		search(m2, r, q[0] + cnt, rx);
	}else{
		search(l, m1, lx, q[1] + cnt);
		search(m2, r, q[0], rx);
	}
}

int find_best(int n){
  	ans = val = -1;
	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:22:2: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   22 |  if(y){
      |  ^~

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