Submission #1029201

#	Time	Username	Problem	Language	Result	Execution time	Memory
1029201		AmirAli_H1	The Big Prize (IOI17_prize)	C++17	20 / 100	44 ms	1980 KiB

prize

// In the name of Allah
 
#include <bits/stdc++.h>
#include "prize.h"
using namespace std;
 
typedef		long long int			ll;
typedef		long double				ld;
typedef		pair<int, int>			pii;
typedef		pair<ll, ll>			pll;
typedef		complex<ld>				cld;
 
#define		all(x)					(x).begin(),(x).end()
#define		len(x)					((ll) (x).size())
#define		F						first
#define		S						second
#define		pb						push_back
#define		sep						' '
#define		endl					'\n'
#define		Mp						make_pair
#define		kill(x)					cout << x << '\n', exit(0)
#define		set_dec(x)				cout << fixed << setprecision(x);
#define		file_io(x,y)			freopen(x, "r", stdin); freopen(y, "w", stdout);
 
const int maxn = 2e5 + 7;
 
int n; pii A[maxn];
mt19937 rng(923232361);
 
void askx(int i) {
	if (A[i].F != -1) return ;
	vector<int> res = ask(i);
	A[i] = Mp(res[0], res[1]);
	return ;
}
 
int find_best(int n) {
	fill(A, A + n, Mp(-1, -1));
	
	if (n <= 5000) {
		for (int i = 0; i < n; i++) {
			askx(i);
			if (A[i].F + A[i].S == 0) return i;
		}
		return -1;
	}
	
	int mx = 0;
	for (int T = 0; T < 300; T++) {
		int i = rng() % n; askx(i);
		if (A[i].F + A[i].S == 0) return i;
		mx = max(mx, A[i].F + A[i].S);
	}
	
	int i = 0;
	while (i < n) {
		askx(i);
		if (A[i].F + A[i].S == 0) return i;
		else if (A[i].F + A[i].S != mx) {
			i++;
			continue;
		}
		
		bool flag = 0;
		int l = i, r = min(n, i + 1024);
		while (r - l > 1) {
			int mid = (l + r) / 2;
			int j = mid; askx(j);
			if (A[j].F + A[j].S == 0) return j;
			if (A[j].F + A[j].S == mx && A[j].F == A[i].F) {
				l = mid;
				if (!flag) break;
			}
			else r = mid;
			flag = 1;
		}
		i = l + 1;
	}
	return -1;
}

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