Submission #169409

#	Time	Username	Problem	Language	Result	Execution time	Memory
169409		AlexLuchianov	Gondola (IOI14_gondola)	C++14	100 / 100	83 ms	6776 KiB

gondola

#include "gondola.h"
#include <algorithm>
#include <iostream>
#include <map>
#include <vector>

using ll = long long;
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#define MAX(a, b) (((a) < (b)) ? (b) : (a))

int const nmax = 250000;
int const modulo = 1000000009;

std::map<int, int> frec;

int valid(int n, int inputSeq[])
{
  for(int i = 0; i < n; i++)
    if(inputSeq[i] <= n) {
      std::rotate(inputSeq, inputSeq + (n + i - inputSeq[i] + 1) % n, inputSeq + n);
      break;
    }

  for(int i = 0; i < n; i++) {
    if(frec[inputSeq[i]] == 1)
      return false;

    frec[inputSeq[i]] = 1;
    if(inputSeq[i] <= n && i + 1 != inputSeq[i])
      return false;
  }
  return true;
}

//----------------------
int seen[1 + nmax];

int replacement(int n, int gondolaSeq[], int replacementSeq[]) {
  for(int i = 0; i < n; i++)
    if(gondolaSeq[i] <= n) {
      std::rotate(gondolaSeq, gondolaSeq + (n + i - gondolaSeq[i] + 1) % n, gondolaSeq + n);
      break;
    }

  int smax = 0;
  for(int i = 0; i < n; i++)
    smax = MAX(smax, gondolaSeq[i]);

  int pos = 0;
  for(int i = 0; i < n; i++)
    if(smax == gondolaSeq[i])
      pos = i + 1;

  for(int i = 0;i < n; i++)
    seen[gondolaSeq[i]] = 1 + i;

  for(int i = n + 1; i <= smax; i++)
    if(seen[i] == 0 || i == smax) {
      replacementSeq[i - n - 1] = pos;
      pos = i;
    } else
      replacementSeq[i - n - 1] = seen[i];

  return smax - n;
}

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

int lgpow(int a, int b){
  if(b == 0)
    return 1;
  else if(b == 1)
    return a;
  else {
    int result = lgpow(a, b / 2);
    if(b % 2 == 0)
      return 1LL * result * result % modulo;
    else
      return 1LL * result * result % modulo * a % modulo;
  }
}

int countReplacement(int n, int inputSeq[])
{
  if(valid(n, inputSeq) == 0)
    return 0;
  else {
    int centered = 0;
    for(int i = 0; i < n; i++)
      if(inputSeq[i] <= n) {
        std::rotate(inputSeq, inputSeq + (n + i - inputSeq[i] + 1) % n, inputSeq + n);
        centered = 1;
        break;
      }

    std::vector<int> v;
    for(int i = 0; i < n; i++)
      if(n < inputSeq[i] )
        v.push_back(inputSeq[i]);
    std::sort(v.begin(), v.end());

    int last = n;
    int result = 1;
    for(int i = 0; i < v.size(); i++){
      result = 1LL * result * lgpow(v.size() - i, v[i] - 1 - last) % modulo;
      last = v[i];
    }
    if(centered == 0)
      return 1LL * n * result % modulo;
    else
      return result;
  }
}

Compilation message (stderr)

gondola.cpp: In function 'int countReplacement(int, int*)':
gondola.cpp:104:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < v.size(); i++){
                    ~~^~~~~~~~~~

• 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