Submission #301254

#	Time	Username	Problem	Language	Result	Execution time	Memory
301254		pacha2880	The Big Prize (IOI17_prize)	C++17	90 / 100	63 ms	384 KiB

prize

#include <bits/stdc++.h>
#include <prize.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define mp				make_pair
#define pb				push_back
#define all(a)			(a).begin(), (a).end()
#define sz(a)			a.size()
#define md(a, b)		((a) % b + b) % b
#define mod(a)			md(a, MOD)
#define srt(a)			sort(all(a))
#define mem(a, h)		memset(a, (h), sizeof(a))
#define f 				first
#define s 				second
#define forn(i, n)			for(int i = 0; i < n; i++)
#define fore(i, b, e)	for(int i = b; i < e; i++)
#define forg(i, b, e, m)	for(int i = b; i < e; i+=m)
//int in(){int r=0,c;for(c=getchar();c<=32;c=getchar());if(c=='-') return -in();for(;c>32;r=(r<<1)+(r<<3)+c-'0',c=getchar());return r;}
 
using namespace std;
//using namespace __gnu_pbds;
 
typedef long long 		ll;
typedef long double ld;	
typedef unsigned long long 		ull;
typedef pair<int, int>  ii;
typedef vector<int>     vi;
typedef vector<ii>      vii;
typedef vector<ll>      vll;
//typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
//find_by_order kth largest  order_of_key <
const int tam = 100010;
const int MOD = 1000000007;
const int MOD1 = 998244353;
const double EPS = 1e-9;
const double PI = acos(-1); 
 
/*int er[] = {4, 4, 4, 4, 3, 4, 4, 4, 4, 4, 2, 3, 4, 4, 4, 4, 4, 4, 4, 4, 3, 4, 4, 3, 1, 4, 4, 4, 4, 2, 4, 4, 4, 3};
vector<int> ar(100034);
int q;
int n;
vector<int> ask(int i)
{
	q++;
	vector<int> res(2, 0);
	fore(j, 0, i)
		res[0] += ar[j] < ar[i];
	fore(j, i + 1, 100034)
		res[1] += ar[j] < ar[i];
	return res;
}
int find_best(int n);
int main()
{
	q = 0;
	fore(i, 0, 100000) ar[i] = 4;
	fore(i, 100000, 100034) ar[i] = er[i - 100000];
	cout<<find_best(100034)<<'\n';
	cout<<q<<'\n';
	return 0;
}*/
int find_best(int n)
{
	int lo = 0, hi = n - 1, mid, res;
	pair<int, pair<int, int>> maxi{0,{0, 0}};
	int q = 0;
	fore(i, 0, 475)
	{
		auto ar = ask(i);
		q++;
		if(ar[0] + ar[1] == 0)
			return i;
      
			if(ar[0] + ar[1] > 40)
			{
				maxi = mp(ar[0] + ar[1], mp(i, ar[0]));
				break;
			}
		maxi = max(maxi, mp(ar[0] + ar[1], mp(i, ar[0])));
	}
	int can = maxi.f, pos = maxi.s.f, le = maxi.s.s;
	//cout<<le<<'\n';
	while(true)
	{
		//cout<<"sdac       "<<pos<<'\n';
		lo = pos + 1, hi = min(n - 1, pos + 1023), res = hi;
		auto er = ask(hi);
		q++;
		if(er[0] + er[1] == 0)
			return hi;
		if(er[0] + er[1] != can || er[0] > le)
		while(lo <= hi)
		{
			mid = (lo + hi) / 2;
			auto ar = ask(mid);
			q++;
			//cout<<mid<<' '<<ar[0]<<' '<<ar[1]<<'\n';
			if(ar[0] + ar[1] != can)
			{
				if(ar[0] + ar[1] == 0)
				{
					return mid;
				}
				res = mid, hi = mid - 1;
			}
			else
			{
				if(ar[0] > le)
					hi = mid - 1;
				else
					lo = mid + 1;
			}
		}
		pos = res;
		while(true)
		{
			auto ar = ask(pos);
			q++;
			if(ar[0] + ar[1] == 0)
			{
 
				return pos;
			}
			if(ar[0] + ar[1] == can)
			{
				le = ar[0];
				break;
			}
			pos++;
		}
	}
}
 
// read the question correctly (is y a vowel? what are the exact constraints?)
// look out for SPECIAL CASES (n=1?) and overflow (ll vs int?) ARRAY OUT OF BOUNDSS2	

Compilation message (stderr)

prize.cpp: In function 'int find_best(int)':
prize.cpp:71:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   71 |   if(ar[0] + ar[1] == 0)
      |   ^~
prize.cpp:74:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   74 |    if(ar[0] + ar[1] > 40)
      |    ^~

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