Submission #782248

#	Time	Username	Problem	Language	Result	Execution time	Memory
782248		ikaurov	Ancient Books (IOI17_books)	C++17	0 / 100	1 ms	212 KiB

books

#include "books.h"
#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
#define all(arr) (arr).begin(), (arr).end()
#define ll long long
#define ld long double
#define pb push_back
#define sz(x) (int)(x).size()
#define fi first
#define se second
#define endl '\n'

long long minimum_walk(std::vector<int> p, int s) {
	int n = sz(p);
  ll ans = 0;
  vector<int> x{0}, sx{0}, sumsz{0};
  for (int i = 0; i < n; i++){
    ans += abs(i - p[i]);
  }
  for (int i = 0, mx = -1; i < n;){
    if (i == p[i] && mx < i){
      int j = i;
      while (j < n && j == p[j]) j++;
      x.pb(j - i);
      sx.pb(sx.back() + x.back());
      sumsz.pb(j);
      i = j;
    }
    else mx = max(mx, p[i]), i++;
  }
  x.pb(0);
  sx.pb(sx.back());
  sumsz.pb(sumsz.back());
  int m = sz(x);
  vector<ll> dp(m);
  ll minval = 0;
  for (int i = 1; i < m; i++){
    dp[i] = minval + sx[i - 1] * 2 + sumsz[i] + x[i];
    minval = min(minval, dp[i] - 2 * sx[i] - sumsz[i]);
  }
  return ans + dp.back();
}

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