Submission #302573

#	Time	Username	Problem	Language	Result	Execution time	Memory
302573		kevinsogo	Gondola (IOI14_gondola)	C++17	100 / 100	39 ms	2688 KiB

gondola

#include "gondola.h"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll mod = 1000000009;

ll mpow(ll b, ll e) {
    if (e == 0) return 1;
    if (e & 1) return mpow(b, e - 1) * b % mod;
    return mpow(b * b % mod, e >> 1);
}

vector<int> arr(int *s, int n, int d = 0) {
    vector<int> v(s, s + n);
    for (int i = 0; i < n; i++) v[i] += d;
    return v;
}

int rotatoize(vector<int>& v) {
    int p = 0, n = v.size();
    while (p < n && v[p] >= n) p++;
    if (p < n) rotate(v.begin(), v.begin() + (p - v[p] + n) % n, v.end());
    return p;
}

int replacement(int n, int gondolaSeq[], int replacementSeq[]) {
    vector<int> gon = arr(gondolaSeq, n, -1);
    vector<int> rep;

    int p = rotatoize(gon);

    vector<int> inds(n), curr(n);
    iota(curr.begin(), curr.end(), 0);
    iota(inds.begin(), inds.end(), 0);
    sort(inds.begin(), inds.end(), [&](int i, int j) { return gon[i] < gon[j]; });
    int spare = n;
    for (int i : inds) {
        while (spare <= gon[i]) {
            rep.push_back(curr[i]);
            curr[i] = spare++;
        }
    }

    for (int i = 0; i < rep.size(); i++) replacementSeq[i] = rep[i] + 1;
    return rep.size();
}

int countReplacement(int n, int inputSeq[]) {
    vector<int> gon = arr(inputSeq, n, -1);
    int p = rotatoize(gon);
    int blanks = 0;
    for (int i = 0; i < n; i++) {
        if (gon[i] < n) {
            if (gon[i] != i) return 0;
        } else blanks++;
    }

    vector<int> vals = gon;
    sort(vals.begin(), vals.end());

    ll ans = blanks == n ? n : 1;
    vector<int> inds(n);
    iota(inds.begin(), inds.end(), 0);
    sort(inds.begin(), inds.end(), [&](int i, int j) { return gon[i] < gon[j]; });
    int spare = n, prev = -1;
    for (int i : inds) {
        if (prev == gon[i]) return 0;
        prev = gon[i];
        if (spare <= gon[i]) {
            ans = ans * mpow(blanks--, max(0, gon[i] - spare)) % mod;
            spare = gon[i] + 1;
        }
    }
    assert(blanks == 0);

    return int(ans);
}

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

Compilation message (stderr)

gondola.cpp: In function 'int replacement(int, int*, int*)':
gondola.cpp:44:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |     for (int i = 0; i < rep.size(); i++) replacementSeq[i] = rep[i] + 1;
      |                     ~~^~~~~~~~~~~~
gondola.cpp:30:9: warning: unused variable 'p' [-Wunused-variable]
   30 |     int p = rotatoize(gon);
      |         ^
gondola.cpp: In function 'int countReplacement(int, int*)':
gondola.cpp:50:9: warning: unused variable 'p' [-Wunused-variable]
   50 |     int p = rotatoize(gon);
      |         ^

• 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