Submission #978915

#	Time	Username	Problem	Language	Result	Execution time	Memory
978915		Amaarsaa	Gondola (IOI14_gondola)	C++14	100 / 100	61 ms	5928 KiB

gondola

#include <iostream>
#include <algorithm>
#include <vector>
#include <set>
#include "gondola.h"
using namespace std;
using ll = long long;
 
ll MOD = 1e9 + 9;
 
int valid(int n, int g[]) {
	set <int> s;
	for (int i = 0; i < n; i++) {
		if (s.count(g[i])) return 0;
		s.insert(g[i]);
	}
	int p = 0;
	for (int i = 0; i < n; i++) if (g[i] <= n) p = (g[i] - i + n) % n;
	for (int i = 0; i < n; i++) if (g[i] <= n && (g[i] - i + n) % n != p) return 0;
	return 1;
}
 
int replacement(int n, int g[], int r[]) {
	int p = 0, cnt = 0, mx = 0;
	vector <int> rev(1e6 + 1, -1);
	vector <int> cur(n, 0);
	for (int i = 0; i < n; i++) {
		if (g[i] <= n) { p = (g[i] - i + n) % n; cnt++; }
		mx = max(mx, g[i]);
		rev[g[i]] = i;
	}
	for (int i = 0; i < n; i++) cur[i] = (i + p) % n;
	cur[(n - p) % n] = n;
	for (int i = n + 1; i <= mx; i++) {
		if (rev[i] == -1) { r[i - n - 1] = cur[rev[mx]]; cur[rev[mx]] = i; }
		else { r[i - n - 1] = cur[rev[i]]; cur[rev[i]] = i; }
	}
	return mx - n;
}
 
ll pow(ll a, int b) {
	ll ret = 1;
	for (int i = 30; i >= 0; i--) {
		ret *= ret; ret %= MOD;
		if (b & (1 << i)) { ret *= a; ret %= MOD; }
	}
	return ret;
}
 
int countReplacement(int n, int g[]) {
	if (!valid(n, g)) return 0;
	ll cnt = 0, ans = 1;
	sort(g, g + n);
	for (int i = 0; i < n; i++) if (g[i] <= n) cnt++;
	if (cnt == 0) ans = n;
	if (cnt == n) return 1;
	ans *= pow(n - cnt, g[cnt] - n - 1);
	ans %= MOD;
	for (int i = cnt + 1; i < n; i++) {
		ans *= pow(n - i, g[i] - g[i - 1] - 1);
		ans %= MOD;
	}
	return ans;
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 10 / 10
• Subtask 4: 5 / 5
• Subtask 5: 10 / 10
• Subtask 6: 20 / 20
• Subtask 7: 5 / 5
• Subtask 8: 15 / 15
• Subtask 9: 15 / 15
• Subtask 10: 10 / 10