Submission #391917

#	Time	Username	Problem	Language	Result	Execution time	Memory
391917		Aldas25	Gondola (IOI14_gondola)	C++14	60 / 100	24 ms	4280 KiB

gondola

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

using namespace std;

#define FOR(i, a, b) for (int i = (a); i <= (b); i++)
#define REP(n) FOR(O, 1, (n))
#define f first
#define s second
#define pb push_back
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<pii> vii;
typedef vector<ll> vl;
typedef vector<int> vi;


int valid(int n, int inputSeq[])
{
    FOR(i, 0, n-1) inputSeq[i]--;

    unordered_set<int> cont;
    FOR(i, 0, n-1) cont.insert(inputSeq[i]);
    if ((int)cont.size() < n) return false;

    int ch = -1;
    FOR(i, 0, n-1) {
        if (inputSeq[i] >= n) continue;
        ch = i;
        break;
    }

    if (ch == -1) return true;

    FOR(i, 0, n-1) {
        int id = (ch+i)%n;
        if (inputSeq[id] >= n) continue;
        int shouldBe = (inputSeq[ch]+i)%n;
        if (inputSeq[id] != shouldBe) return false;
    }

    return true;
}

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

int replacement(int n, int inputSeq[], int replacementSeq[])
{
    FOR(i, 0, n-1) inputSeq[i]--;

    int l = 0;

    int ch = 0;
    FOR(i, 0, n-1) {
        if (inputSeq[i] >= n) continue;
        ch = i;
        break;
    }

    int cur[n];

    cur[ch] = (inputSeq[ch] < n ? inputSeq[ch] : 0);

    FOR(i, 0, n-1) {
        int id = (ch+i)%n;
        int shouldBe = (cur[ch]+i)%n;
        cur[id] = shouldBe;
    }

    vii seq;
    FOR(i, 0, n-1) {
        seq.pb({inputSeq[i], i});
    }
    sort(seq.begin(), seq.end());

    int crAdd = n;
    for (auto p : seq) {
        int id = p.s;
        while (cur[id] < inputSeq[id]) {
            replacementSeq[l] = cur[id]+1;
            cur[id] = crAdd;
            crAdd++;
            l++;
        }
    }

    return l;
}

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

const ll MOD = 1e9+7;

ll pwr (ll a, ll p) {
    if (p == 0) return 1ll;
    if (p == 1) return a%MOD;
    ll ret = pwr(a, p/2);
    ret = (ret*ret)%MOD;
    if (p%2 == 1) ret *= a%MOD;
    return ret%MOD;
}

int countReplacement(int n, int inputSeq[])
{
    if (!valid(n, inputSeq)) return 0;

    ll ans = 1;

    FOR(i, 0, n-1) inputSeq[i]--;

    int ch = 0;
    FOR(i, 0, n-1) {
        if (inputSeq[i] >= n) continue;
        ch = i;
        break;
    }

    vii seq;
    FOR(i, 0, n-1) {
        seq.pb({inputSeq[i], i});
    }
    sort(seq.begin(), seq.end());

    ll rem = n;
    ll lst = n-1;
    for (auto p : seq) {
        int id = p.s;
        if (inputSeq[id] >= n) {
            ll cnt = inputSeq[id] - lst + 1;
            ll cr = pwr(rem, cnt);
            ans = (ans*cr)%MOD;
            lst = inputSeq[id];
        }
        rem--;
    }

    return ans;
}

Compilation message (stderr)

gondola.cpp: In function 'int countReplacement(int, int*)':
gondola.cpp:111:9: warning: variable 'ch' set but not used [-Wunused-but-set-variable]
  111 |     int ch = 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: 0 / 15
• Subtask 9: 0 / 15
• Subtask 10: 0 / 10