Submission #469585

#	Time	Username	Problem	Language	Result	Execution time	Memory
469585		Soumya1	Gondola (IOI14_gondola)	C++17	60 / 100	49 ms	4784 KiB

gondola

#include "gondola.h"
#include <bits/stdc++.h>
using namespace std;
const int mod = 1e9 + 7;
int valid(int n, int a[]) {
  bool ok = true;
  map<int, bool> mp;
  for (int i = 0; i < n; i++) {
    ok &= (!mp[a[i]]);
    mp[a[i]] = true;
  }
  int pos = -1, val = -1;
  for (int i = 0; i < n; i++) {
    if (a[i] <= n) {
      val = a[i];
      pos = i;
      break;
    }
  }
  val++;
  if (val > n) val = 1;
  for (int i = pos + 1; i < n; i++) {
    if (a[i] <= n) {
      ok &= (a[i] == val);
    }
    val++;
    if (val > n) val = 1;
  }
  for (int i = 0; i < pos; i++) {
    if (a[i] <= n) {
      ok &= (a[i] == val);
    }
    val++;
    if (val > n) val = 1;
  }
  return (int) ok;
}
int replacement(int n, int a[], int ans[]) {
  int pos = -1, val = -1;
  for (int i = 0; i < n; i++) {
    if (a[i] <= n) {
      pos = i;
      val = a[i];
      break;
    }
  }
  vector<pair<int, int>> v;
  for (int i = 0; i < n; i++) {
    if (a[i] > n) v.push_back({a[i], i});
  }
  if (pos != -1) {
    for (int i = pos; i < n; i++) {
      a[i] = val++;
      if (val > n) val = 1;
    }
    for (int i = 0; i < pos; i++) {
      a[i] = val++;
      if (val > n) val = 1;
    }
  } else {
    for (int i = 0; i < n; i++) a[i] = i + 1;
  }
  int ptr = 0;
  sort(v.begin(), v.end());
  int cur = n + 1;
  for (int i = 0; i < v.size(); i++) {
    while (cur <= v[i].first) {
      ans[ptr++] = a[v[i].second];
      a[v[i].second] = cur++;
    }
  }
  return ptr;
}
int bigmod(int a, int b) {
  int res = 1;
  while (b > 0) {
    if (b & 1) res = (1LL * res * a) % mod;
    a = (1LL * a * a) % mod, b >>= 1;
  }
  return res;
}
int countReplacement(int n, int a[]) {
  if (!valid(n, a)) return 0;
  int pos = -1, val = -1;
  for (int i = 0; i < n; i++) {
    if (a[i] <= n) {
      pos = i;
      val = a[i];
      break;
    }
  }
  sort(a, a + n);
  int ans = 1;
  int taken = 0;
  int nn = n;
  for (int i = 0; i < n; i++) {
    if (a[i] > n) {
      ans = (1LL * ans * bigmod(nn, a[i] - n - 1)) % mod;
      taken++;
    }
    nn--;
  }
  if (pos == -1) {
    for (int i = 1; i <= n; i++) {
      ans = (1LL * ans * i) % mod;
    }
  }
  return ans;
}

Compilation message (stderr)

gondola.cpp: In function 'int replacement(int, int*, int*)':
gondola.cpp:66:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   66 |   for (int i = 0; i < v.size(); i++) {
      |                   ~~^~~~~~~~~~
gondola.cpp: In function 'int countReplacement(int, int*)':
gondola.cpp:84:17: warning: variable 'val' set but not used [-Wunused-but-set-variable]
   84 |   int pos = -1, val = -1;
      |                 ^~~

• 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