Submission #656847

#	Time	Username	Problem	Language	Result	Execution time	Memory
656847		happypotato	Gondola (IOI14_gondola)	C++17	100 / 100	35 ms	5004 KiB

gondola

#include "gondola.h"
#include <bits/stdc++.h>
using namespace std;

int valid(int n, int inputSeq[])
{
	int seq[n];
	set<int> s;
	for (int i = 0; i < n; i++) {
		seq[i] = (inputSeq[i] <= n ? inputSeq[i] : -1);
		if (s.find(inputSeq[i]) != s.end()) return 0;
		s.insert(inputSeq[i]);
	}
	int samemod = -1;
	for (int i = 0; i < n; i++) {
		if (seq[i] == -1) continue;
		int curmod = (seq[i] + n - i) % n;
		if (samemod == -1) samemod = curmod;
		else if (samemod != curmod) return 0;
	}
	return 1;
}

//----------------------

int replacement(int n, int gondolaSeq[], int replacementSeq[])
{
	vector<pair<int, int>> v;
	v.push_back({n, -1});
	int samemod = 0;
	for (int i = 0; i < n; i++) {
		if (gondolaSeq[i] <= n) {
			samemod = (gondolaSeq[i] + n - i) % n;
		} else {
			v.push_back({gondolaSeq[i], i});
		}
	}
	sort(v.begin(), v.end());
	int ptr = 0;
	for (int i = 1; i < int(v.size()); i++) {
		int ori = (v[i].second + samemod) % n;
		if (ori == 0) ori = n;
		replacementSeq[ptr++] = ori;
		for (int j = v[i - 1].first + 2; j <= v[i].first; j++) {
			replacementSeq[ptr++] = j - 1;
		}
	}
	return ptr;
}

//----------------------
const long long MOD = 1e9 + 9;
long long bigmod(long long b, int p) {
	long long ans = 1;
	while (p) {
		if (p & 1) ans = (ans * b) % MOD;
		p >>= 1;
		b = (b * b) % MOD;
	}
	return ans;
}
int countReplacement(int n, int inputSeq[])
{
	vector<int> v;
	v.push_back(n);
	int samemod = 0;
	for (int i = 0; i < n; i++) {
		if (inputSeq[i] > n) {
			v.push_back(inputSeq[i]);
		}
	}
	sort(v.begin(), v.end());
	int m = v.size();
	long long ans = (m == n + 1 ? n : 1);
	for (int i = 1; i < m; i++) {
		ans = (ans * bigmod(m - i, (v[i] - v[i - 1] - 1))) % MOD;
	}
	return ans;
}

Compilation message (stderr)

gondola.cpp: In function 'int countReplacement(int, int*)':
gondola.cpp:66:6: warning: unused variable 'samemod' [-Wunused-variable]
   66 |  int samemod = 0;
      |      ^~~~~~~

• 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