Submission #1325958

#	Time	Username	Problem	Language	Result	Execution time	Memory
1325958		crispxx	Gondola (IOI14_gondola)	C++20	65 / 100	35 ms	4972 KiB

gondola

#include "gondola.h"

#include <bits/stdc++.h>

using namespace std;

using ll = long long;

const int mod = 1e9 + 9;

int mul(int a, int b) {
	return a * 1LL * b % mod;
}

int binpow(int a, int b) {
	int res = 1;
	
	while(b > 0) {
		if(b & 1) res = mul(res, a);
		a = mul(a, a);
		b >>= 1;
	}
	
	return res;
}

int valid(int n, int s[]) {
	set<int> st(s, s + n);
	
	if( (int)st.size() != n ) return false;
	
	st.clear();
	
	for(int i = 0; i < n; i++) {
		s[i]--;
		
		if(s[i] < n) {
			st.emplace((i - s[i] + n) % n);
		}
	}
	
	return (int)st.size() <= 1;
}

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

int replacement(int n, int s[], int r[]) {
	return -1;
}

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

int countReplacement(int n, int s[]) {
	if( !valid(n, s) ) return 0;
	
	vector<int> b;
	
	for(int i = 0; i < n; i++) {
		if(s[i] >= n) {
			b.push_back(s[i]);
		}
	}
	
	b.push_back(n - 1);
	
	sort(b.begin(), b.end());
	
	// for(auto &x : b) cout << x + 1 << ' ';
	// cout << '\n';
	                                                                                                                                                                                                                                                                  
	int ans = 1;
	
	for(int i = 1; i < (int)b.size(); i++) {
		int aval = b.size() - i;
		int k = b[i] - b[i - 1] - 1;
		// cout << aval << ' ' << k << '\n';
		ans = mul( ans, binpow(aval, k) );
	}
	
	if( (int)b.size() == n + 1 ) {
		ans = mul(ans, n);
	}
	
	return ans;
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 10 / 10
• Subtask 4: 0 / 5
• Subtask 5: 0 / 10
• Subtask 6: 0 / 20
• Subtask 7: 5 / 5
• Subtask 8: 15 / 15
• Subtask 9: 15 / 15
• Subtask 10: 10 / 10