Submission #1202474

#	Time	Username	Problem	Language	Result	Execution time	Memory
1202474		TahirAliyev	Gondola (IOI14_gondola)	C++20	100 / 100	35 ms	6104 KiB

gondola

#include "gondola.h"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
const int MOD = 1e9 + 9;

int valid(int n, int arr[]){
    set<ll> s, s2;
    for(int i = 0; i < n; i++){
        if(arr[i] <= n) s.insert((arr[i] - i + n) % n);
        s2.insert(arr[i]);
    }
    return (s2.size() == n && s.size() <= 1);
}

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

int replacement(int n, int a[], int replacementSeq[])
{
    ll st = -1, b[n];
    for (ll i = 0; i < n; i++)
        if (a[i] <= n)
            st = i;
    if (st == -1)
        iota(b, b + n, 1);
    else
    {
        b[st] = a[st];
        for (ll i = st + 1; i < st + n; i++)
            b[i % n] = b[(i - 1 + n) % n] % n + 1;
    }
    ll ptr = 0, mx = max_element(a, a + n) - a;
    ll ind[a[mx] + 1];
    for (ll i = 0; i <= a[mx]; i++)
        ind[i] = -1;
    for (ll i = 0; i < n; i++)
        ind[a[i]] = i;
    for (ll i = n + 1; i <= a[mx]; i++)
        if (ind[i] != -1)
            replacementSeq[ptr++] = b[ind[i]], b[ind[i]] = i;
        else
            replacementSeq[ptr++] = b[mx], b[mx] = i;
    return ptr;
}

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

ll binpow(ll a, ll b){
    a %= MOD;
    ll res = 1;
    while(b){
        if(b & 1) res = res * a % MOD;
        b /= 2; 
        a = a * a % MOD;
    }
    return res;
}

int countReplacement(int n, int arr[]){
    if(!valid(n, arr)) return 0;
    vector<int> v;
    for(int i = 0; i < n; i++){
        if(arr[i] > n) v.push_back(arr[i]);
    } 
    sort(v.begin(), v.end());
    v.insert(v.begin(), n);
    ll ans = 1;
    for(int i = 1; i < v.size(); i++){
        ans = ans * binpow(v.size() - i, v[i] - v[i - 1] - 1) % MOD;
    }
    if(v.size() - 1 == n) ans = ans * n % 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