Submission #129467

#	Time	Username	Problem	Language	Result	Execution time	Memory
129467		antimirage	Gondola (IOI14_gondola)	C++14	60 / 100	27 ms	6108 KiB

gondola

#include "gondola.h"
//#include "grader.cpp"
#include <bits/stdc++.h>

using namespace std;

const int N = 1e6 + 5;

int b[N], ind[N], mx, sz, cnt[N], mod = 1e9 + 9;

int valid(int n, int a[]) {
	int pos = -1;
	
	for (int i = 0; i < n; i++) {
		if (a[i] <= n) {
			pos = i;
		}
		cnt[a[i]]++;
		
		if (cnt[a[i]] > 1)
			return 0;
	}
	if (pos == -1) {
		return 1;
	} else {
		assert(a[pos] <= n);
		int cn = a[pos];
		for (int i = (pos + 1) % n; i != pos; i = (i + 1) % n) {
			cn++;
			if (cn > n)
				cn -= n;
			if (a[i] > n) {
				continue;
			}
			if (a[i] != cn) {
				return 0;
			}
		}
	}
	return 1;
}
int replacement(int n, int a[], int ans[]) {
	memset(ind, -1, sizeof(ind));
	int pos = -1;
	
	for (int i = 0; i < n; i++) {
		if (a[i] <= n) {
			pos = i;
		}
		if (a[i] > a[mx]) {
			mx = i;
		}
		ind[a[i]] = i;
	}
	if (pos == -1) {
		for (int i = 0; i < n; i++) {
			b[i] = i + 1;
		}
	}
	else {
		int cn = a[pos];
		b[pos] = a[pos];
		for (int i = (pos + 1) % n; i != pos; i = (i + 1) % n) {
			cn++;
			if (cn > n)
				cn -= n;
			b[i] = cn;
		}
	}
	for (int i = n + 1; i <= a[mx]; i++) {
		if (ind[i] == -1) {
			ans[sz++] = b[mx];
			b[mx] = i;
		}
		else {
			ans[sz++] = b[ind[i]];
			b[ind[i]] = i;
		}
	}
	return sz;
}

int countReplacement(int n, int a[]) {
	if (valid(n, a) == 0)
		return 0;
		
	int pos = -1;
	
	long long res = 1, val = 1;
	
	for (int i = 0; i < n; i++) {
		if (a[i] <= n) {
			pos = i;
		}
	}
	if (pos == -1) {
		for (int i = 0; i < n; i++) {
			b[i] = i + 1;
			res *= (i + 1);
			res %= mod;
		}
	} else {
		int cn = a[pos];
		b[pos] = a[pos];
		for (int i = (pos + 1) % n; i != pos; i = (i + 1) % n) {
			cn++;
			if (cn > n)
				cn -= n;
			b[i] = cn;
		}
		sort(a, a + n);
		int j = 0;
		for (int i = n + 1; i <= a[n - 1]; i++) {
			while (a[j] < i)
				j++;
			if (ind[i] == -1) {
				res *= (n - j);
				res %= mod;
			}
		}
	}
	return res;
}

Compilation message (stderr)

gondola.cpp: In function 'int countReplacement(int, int*)':
gondola.cpp:89:21: warning: unused variable 'val' [-Wunused-variable]
  long long res = 1, val = 1;
                     ^~~

• 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: 0 / 15
• Subtask 9: 0 / 15
• Subtask 10: 0 / 10