Submission #558044

#	Time	Username	Problem	Language	Result	Execution time	Memory
558044		aryan12	The Big Prize (IOI17_prize)	C++17	0 / 100	5 ms	440 KiB

prize

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

const int MAXN = 450;
vector<array<int, 3> > results;
int N;

bool cmp(array<int, 3> a, array<int, 3> b)
{
	return ((a[0] + a[1]) > (b[0] + b[1]));
}

int DivideAndConquer(int l, int r)
{
	if(l > r)
	{
		return -1;
	}
	if(l == 0 && r == N - 1)
	{
		int value1, value2;
		if(results[0][0] != 0)
		{
			value1 = DivideAndConquer(l, results[0][2] - 1);
		}
		if(results[0][1] != 0)
		{
			value2 = DivideAndConquer(results[0][2] + 1, r);
		}
		if(results[0][0] == 0 && results[0][1] == 0)
		{
			return results[0][2];
		}
		if(value1 == -1)
		{
			return value2;
		}
		return value1;
	}
	int mid = (l + r) >> 1;
	vector<int> reply = ask(mid);
	if(reply[0] + reply[1] == 0)
	{
		return mid;
	}
	int value1, value2;
	if(reply[0] != 0)
	{
		value1 = DivideAndConquer(l, mid - 1);
	}
	if(reply[1] != 0)
	{
		value2 = DivideAndConquer(mid + 1, r);
	}
	if(value1 == -1 && value2 == -1)
	{
		return -1;
	}
	if(value1 == -1)
	{
		return value2;
	}
	return value1;
}

int find_best(int n)
{
	N = n;
	int mid = n / 2;
	vector<array<int, 3> > results;
	for(int i = max(0, mid - MAXN / 2); i < min(n, mid + MAXN / 2 + 1); i++)
	{
		vector<int> reply = ask(i);
		if(reply[0] + reply[1] == 0)
		{
			return i;
		}
		results.push_back({reply[0], reply[1], i});
	}
	sort(results.begin(), results.end(), cmp);
	return DivideAndConquer(0, n - 1);
}

Compilation message (stderr)

prize.cpp: In function 'int DivideAndConquer(int, int)':
prize.cpp:47:14: warning: 'value2' may be used uninitialized in this function [-Wmaybe-uninitialized]
   47 |  int value1, value2;
      |              ^~~~~~
prize.cpp:60:2: warning: 'value1' may be used uninitialized in this function [-Wmaybe-uninitialized]
   60 |  if(value1 == -1)
      |  ^~
prize.cpp:22:15: warning: 'value2' may be used uninitialized in this function [-Wmaybe-uninitialized]
   22 |   int value1, value2;
      |               ^~~~~~
prize.cpp:35:3: warning: 'value1' may be used uninitialized in this function [-Wmaybe-uninitialized]
   35 |   if(value1 == -1)
      |   ^~

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