Submission #103962

#	Time	Username	Problem	Language	Result	Execution time	Memory
103962		RockyB	The Big Prize (IOI17_prize)	C++17	90 / 100	87 ms	512 KiB

prize

/// In The Name Of God

#include <bits/stdc++.h>
#ifndef IOI2018
#include "prize.h"
#endif

#define f first
#define s second

#define pb push_back
#define pp pop_back
#define mp make_pair

#define sz(x) (int)x.size()
#define sqr(x) ((x) * 1ll * (x))
#define all(x) x.begin(), x.end()

#define rep(i, l, r) for (int i = (l); i < (r); i++)
#define per(i, l, r) for (int i = (l); i >= (r); i--)

#define Kazakhstan ios_base :: sync_with_stdio(0), cin.tie(0), cout.tie(0);

#define nl '\n'
#define ioi exit(0);

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;

const int N = (int)5e5 + 7;
const int inf = (int)1e9 + 7;
const int mod = (int)1e9 + 7;
const ll linf = (ll)1e18 + 7;

const int dx[] = {-1, 0, 1, 0, 1, -1, -1, 1};
const int dy[] = {0, 1, 0, -1, 1, -1, 1, -1};

using namespace std;

namespace com {
	static const int max_q = 10000;
	static int n;
	static int query_count = 0;
	static vector<int> g;
	static vector<vector<int> > rank_count;

}

namespace grader {
	using namespace com;
	vector<int> ask(int i) {
		query_count++;
		if(query_count > max_q) {
			cerr << "Query limit exceeded" << endl;
			exit(0);
		}

		if(i < 0 || i >= n) {
			cerr << "Bad index: " << i << endl;
			exit(0);
		}

		vector<int> res(2);
		res[0] = rank_count[g[i] - 1][i + 1];
		res[1] = rank_count[g[i] - 1][n] - res[0];
		return res;
	}
}
#ifdef IOI2018
using namespace grader;
#endif

int solve(int p, int n) {
	while (p < n) {
		int l = p + 1, r = n - 1, res = p;
		vector <int> cur = ask(p);
		while (l <= r) {
			int mid = l + r >> 1;
			vector <int> now = ask(mid);
			if ((now[0] + now[1] == cur[0] + cur[1]) && now[0] == cur[0]) {
				res = mid, l = mid + 1;
			}
			else r = mid - 1;
		}
		++res;
		while (res < n) {
			vector <int> now = ask(res);
			if (!max(now[0], now[1])) return res;
			if (now[0] + now[1] == cur[0] + cur[1]) break;
			++res;
		}
		p = res;
	}
	assert(0);
}
int find_best(int n) {
	int mx = -1, p = -1;
	rep(i, 0, min(500, n)) {
		#ifndef IOI2018
		vector <int> a = ask(i);
		#endif
		#ifdef IOI2018
		vector <int> a = grader :: ask(i);
		#endif
		if (a[0] + a[1] == 0) return i;
		if (a[0] + a[1] > mx) {
			mx = a[0] + a[1];
			p = i;
		}
	}
	return solve(p, n);
} 

namespace read {
	using namespace com;
	void read() {
		cin >> n;
		g.resize(n);
		for(int i = 0; i < n; i++) {
			cin >> g[i];
			if(g[i] < 1) {
				cerr << "Invalid rank " << g[i] << " at index " << i << endl;
				exit(0);
			}
		}

		int max_rank = *max_element(g.begin(), g.end());
		rank_count.resize(max_rank + 1, vector<int>(n + 1, 0));
		for(int r = 0; r <= max_rank; r++) {
			for(int i = 1; i <= n; i++) {
				rank_count[r][i] = rank_count[r][i - 1];
				if(g[i - 1] == r)
				  rank_count[r][i]++;
			}
		}

		for(int i = 0; i <= n; i++)
			for(int r = 1; r <= max_rank; r++)
				rank_count[r][i] += rank_count[r - 1][i];

		int res = find_best(n);
		cout << res;
		ioi
		cout << res << endl << "Query count: " << query_count << endl;
		ioi
	}
}

#ifdef IOI2018
int main() {
	#ifdef IOI2018
		freopen ("in.txt", "r", stdin);
		freopen ("D.out", "w", stdout);
	#endif
	read :: read();
}
#endif

Compilation message (stderr)

prize.cpp: In function 'int solve(int, int)':
prize.cpp:79:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
    int mid = l + r >> 1;
              ~~^~~

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