Submission #574552

#	Time	Username	Problem	Language	Result	Execution time	Memory
574552		valerikk	The Big Prize (IOI17_prize)	C++17	90 / 100	124 ms	11316 KiB

prize

#include "prize.h"
#include <bits/stdc++.h>
 
using namespace std;
 
mt19937 rnd(239);
 
namespace {
 
int mx_cnt;
 
}
 
vector<vector<int>> mem;
 
vector<int> mask(int i) {
	return mem[i] == vector<int>{-1, -1} ? mem[i] = ask(i) : mem[i];
}
 
int solve(int l, int r) {
	if (l > r) 
		return -1;
 
	if (l == r) {
		auto a = mask(l);
		if (a[0] + a[1] == 0)
			return l;
		return -1;
	}
 
	auto al = mask(l);
	auto ar = mask(r);
 
	if (al[0] + al[1] == 0)
		return l;
	if (ar[0] + ar[1] == 0)
		return r;
 
	if (al[0] + al[1] == ar[0] + ar[1] && al[0] == ar[0]) 
		return -1;
 
	int m = (l + r) / 2;
 
	int res = solve(l, m);
	if (res == -1)
		res = solve(m + 1, r);
	return res;
}	
 
int find_best(int n) {
	mem.resize(n, vector<int>{-1, -1});
	return solve(0, n - 1);
}

Compilation message (stderr)

prize.cpp:10:5: warning: '{anonymous}::mx_cnt' defined but not used [-Wunused-variable]
   10 | int mx_cnt;
      |     ^~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 70 / 80