Submission #1075690

#	Time	Username	Problem	Language	Result	Execution time	Memory
1075690		edogawa_something	Ancient Books (IOI17_books)	C++17	50 / 100	84 ms	15968 KiB

books

#include "books.h"
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> vii;
typedef pair<ll,ll> pii;
#define F first
#define S second
#define all(v) v.begin(),v.end()
#define pb push_back
ll n;
bool vis[2000000];
long long minimum_walk(vector<int> p, int s) {
  n=p.size();
  ll res=0;
  bool chk=1;
  for(int i=0;i<n;i++) {
    if(p[i]!=i)
      chk=0;
  }
  if(chk)
    return 0;
  ll cnt=0;
  for(int i=0;i<n;i++) {
    if(p[i]>=i) {
      cnt++;
    }
    vis[p[i]]=1;
    if(vis[i])
      cnt--;
    res+=2*cnt;
    if(cnt==0)
      res+=2;
  }
  res-=2;
  for(int i=n-1;i>=0;i--) {
    if(p[i]==i)
      res-=2;
    else
      break;
  }
  return res;
}

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