Submission #385833

#	Time	Username	Problem	Language	Result	Execution time	Memory
385833		ParsaAlizadeh	Gondola (IOI14_gondola)	C++17	75 / 100	70 ms	4588 KiB

gondola

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

typedef long long ll;

int const N = 2.5e5 + 10;
int const MOD = 1e9 + 9;

constexpr ll pw(ll a, ll b, ll mod) {
    return (!b    ? 1 :
            b & 1 ? a * pw(a * a % mod, b / 2, mod) % mod :
                    pw(a * a % mod, b / 2, mod));
}

int valid(int n, int inputSeq[]) {
    int st = -1;
    map<int, bool> mark;
    for (int i = 0; i < n; i++) {
        if (inputSeq[i] <= n) {
            if (st == -1)
                st = (inputSeq[i] - 1) - i + n;
            else if (inputSeq[i] - 1 != (st + i) % n)
                return 0;
        }
        if (mark[inputSeq[i]])
            return 0;
        mark[inputSeq[i]] = true;
    }
    return 1;
}

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

int replacement(int n, int gondolaSeq[], int replacementSeq[]) {
    int st = 0, l = 0;
    for (int i = 0; i < n; i++) {
        if (gondolaSeq[i] <= n)
            st = (gondolaSeq[i] - 1) - i + n;
        l = max(l, gondolaSeq[i]);
    }
    vector<int> ind(l + 1, -1), tmp(n, 0);
    for (int i = 0; i < n; i++) {
        ind[gondolaSeq[i]] = i;
        tmp[i] = 1 + (st + i) % n;
    }
    int ptr = 0;
    for (int i = n + 1; i <= l; i++) {
        while (ptr < n && tmp[ptr] == gondolaSeq[ptr])
            ptr++;
        int j = (ind[i] != -1 ? ind[i] : ptr);
        replacementSeq[i - n - 1] = tmp[j];
        tmp[j] = i;
    }
    return l - n;
}

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

int countReplacement(int n, int inputSeq[]) {
    if (!valid(n, inputSeq))
        return 0;
    int l = *max_element(inputSeq, inputSeq + n);
    set<int> st;
    for (int i = 0; i < n; i++) 
        if (inputSeq[i] > n)
            st.insert(inputSeq[i]);
    int t = st.size(), last = n;
    ll ans = 1;
    for (int x : st) {
        ans = ans * pw(t, x - last - 1, MOD) % MOD;
        t--;
        last = x;
    }
    return ans;
}

Compilation message (stderr)

gondola.cpp: In function 'int countReplacement(int, int*)':
gondola.cpp:63:9: warning: unused variable 'l' [-Wunused-variable]
   63 |     int l = *max_element(inputSeq, inputSeq + n);
      |         ^

• 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: 0 / 15
• Subtask 10: 0 / 10