Submission #780391

#	Time	Username	Problem	Language	Result	Execution time	Memory
780391		vjudge1	Ancient Books (IOI17_books)	C++17	50 / 100	871 ms	52580 KiB

books

#include <bits/stdc++.h>
#define all(x) (x).begin(),(x).end()
using namespace std;

using ll = long long;
using ld = long double;

//#define int ll
#define sz(x) ((int)(x).size())

using pii = pair<int,int>;
using tii = tuple<int,int,int>;

const int nmax = 1e6 + 5;

int n;

long long minimum_walk(std::vector<int> p, int s) {
  n = sz(p);
  vector<int> col(n, 0);
  vector<int> reqs(n + 2, 0);
  int flag = 0;
  
  multiset<int> lhf;
  
  ll sum = 0;
  
  for(int i = 0; i < n; i++) {
    if(col[i] == 0) {
      flag++;
      int x = i, cnt = 0;
      set<int> vals;
      while(col[x] != flag) {
        col[x] = flag;
        sum += abs(x - p[x]);
        x = p[x];
        cnt++;
        vals.emplace(x);
      }
      int L = *vals.begin();
      int R = *vals.rbegin();
      reqs[L]++;
      reqs[R]--;
      
    }
  }
  for(int i = 1; i <= n; i++)
    reqs[i] += reqs[i - 1];
  int l = 0, r = n - 1;
  while(l < s && p[l] == l) l++;
  while(r > s && p[r] == r) r--;
  r--;
  if(s != 0)
    assert(l & 16);
  

  ll mn = 0;
  for(int i = l; i <= r; i++) mn += reqs[i] == 0;
  return sum + mn * 2;
}

/**
      Anul asta se da centroid.
-- Surse oficiale
*/

• Subtask 1: 12 / 12
• Subtask 2: 10 / 10
• Subtask 3: 28 / 28
• Subtask 4: 0 / 20
• Subtask 5: 0 / 30