Submission #60187

#	Time	Username	Problem	Language	Result	Execution time	Memory
60187		Flugan42	Sorting (IOI15_sorting)	C++14	100 / 100	425 ms	15876 KiB

sorting

#include "sorting.h"
#include <bits/stdc++.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef vector<ll> vi;
typedef pair<ll,ll> ii;
typedef vector<ii> vii;
#define rep(i,a,b) for(int i = a; i < b; i++)
#define per(i,a,b) for(int i = a; i >= b; i--)
#define inf 9223372036854775807
#define all(x) x.begin(),x.end()
#define sz(x) (ll)(x).size()
#define trav(a,x) for(auto& a : x)

int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
  ll lo = -1, hi = N, mid;
  while (lo+1 < hi){
    mid = (lo+hi)/2;
    vi last; last.assign(N,0);
    rep(i,0,N) last[i] = S[i];
    rep(i,0,mid){
      ll t1 = last[X[i]];
      ll t2 = last[Y[i]];
      last[Y[i]] = t1;
      last[X[i]] = t2;
    }
    vi inv; inv.assign(N,0);
    rep(i,0,N) inv[last[i]] = i;
    ll cur = 0;
    rep(i,0,mid){
      while (cur < N && inv[cur] == cur) cur++;
      if (cur == N) break;
      ll s = last[cur],ls = inv[cur];
      last[ls] = s;
      last[cur] = cur;
      inv[cur] = cur;
      inv[s] = ls;
    }
    bool check = true;
    rep(i,0,N) if (inv[i] != i) check = false;
    if (check) {
      hi = mid;
    } else {
      lo = mid;
    }
  }
  if (hi == 0){
    bool check = true;
    rep(i,0,N) if (S[i] != i) check = false;
    if (check) return 0;
    else hi = 1;
  }
  vi last; last.assign(N,0);
  rep(i,0,N) last[i] = S[i];
  rep(i,0,hi){
    ll t1 = last[X[i]];
    ll t2 = last[Y[i]];
    last[Y[i]] = t1;
    last[X[i]] = t2;
  }
  vi inv; inv.assign(N,0);
  rep(i,0,N) inv[last[i]] = i;
  ll cur = 0;
  vii swap;
  rep(i,0,hi){
    while (cur < N && inv[cur] == cur) cur++;
    if (cur == N) break;
    ll s = last[cur],ls = inv[cur];
    swap.push_back(make_pair(s,cur));
    last[ls] = s;
    last[cur] = cur;
    inv[cur] = cur;
    inv[s] = ls;
  }
  while (sz(swap) < hi) swap.push_back(make_pair(0,0));
  last.assign(N,0);
  inv.assign(N,0);
  rep(i,0,N) last[i] = S[i];
  rep(i,0,N) inv[last[i]] = i;
  rep(i,0,hi){
    ll t1 = last[X[i]];
    ll t2 = last[Y[i]];
    last[Y[i]] = t1;
    last[X[i]] = t2;
    inv[t1] = Y[i];
    inv[t2] = X[i];
    //
    P[i] = inv[swap[i].first];
    Q[i] = inv[swap[i].second];
    last[P[i]] = swap[i].second;
    last[Q[i]] = swap[i].first;
    inv[swap[i].first] = Q[i];
    inv[swap[i].second] = P[i];
  }
	return hi;
}

static char _buffer[1024];
static int _currentChar = 0;
static int _charsNumber = 0;
static FILE *_inputFile, *_outputFile;

static inline int _read() {
    if (_charsNumber < 0) {
        exit(1);
    }
    if (!_charsNumber || _currentChar == _charsNumber) {
        _charsNumber = (int)fread(_buffer, sizeof(_buffer[0]), sizeof(_buffer), _inputFile);
        _currentChar = 0;
    }
    if (_charsNumber <= 0) {
        return -1;
    }
    return _buffer[_currentChar++];
}

static inline int _readInt() {
    int c, x, s;
    c = _read();
    while (c <= 32) c = _read();
    x = 0;
    s = 1;
    if (c == '-') {
        s = -1;
        c = _read();
    }
    while (c > 32) {
        x *= 10;
        x += c - '0';
        c = _read();
    }
    if (s < 0) x = -x;
    return x;
}

Compilation message (stderr)

sorting.cpp: In function 'int findSwapPairs(int, int*, int, int*, int*, int*, int*)':
sorting.cpp:92:29: warning: conversion to 'int' from '__gnu_cxx::__alloc_traits<std::allocator<long long int> >::value_type {aka long long int}' may alter its value [-Wconversion]
     P[i] = inv[swap[i].first];
                             ^
sorting.cpp:93:30: warning: conversion to 'int' from '__gnu_cxx::__alloc_traits<std::allocator<long long int> >::value_type {aka long long int}' may alter its value [-Wconversion]
     Q[i] = inv[swap[i].second];
                              ^
sorting.cpp:99:9: warning: conversion to 'int' from 'll {aka long long int}' may alter its value [-Wconversion]
  return hi;
         ^~
sorting.cpp:19:39: warning: unused parameter 'M' [-Wunused-parameter]
 int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
                                       ^
sorting.cpp: At global scope:
sorting.cpp:105:27: warning: '_outputFile' defined but not used [-Wunused-variable]
 static FILE *_inputFile, *_outputFile;
                           ^~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 12 / 12
• Subtask 3: 16 / 16
• Subtask 4: 18 / 18
• Subtask 5: 20 / 20
• Subtask 6: 26 / 26