Submission #874039

#	Time	Username	Problem	Language	Result	Execution time	Memory
874039		vjudge1	Lamps (JOI19_lamps)	C++17	6 / 100	356 ms	89704 KiB

lamp

#include <bits/stdc++.h>
#define file_io freopen("input.txt", "r", stdin);freopen("output.txt", "w", stdout);
#define fast_io ios::sync_with_stdio(false);cin.tie(0);
#define what(x) cerr << #x << " is " << x << '\n';
#define kill(x) {cout << x << '\n'; return 0;}
#define all(x) (x).begin(), (x).end()
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pb push_back
#define ll long long
#define F first
#define S second
const ll inf = 1e18, mod = 1e9 + 7, delta = 1e9 + 9, SQ = 450, P = 6065621; //998244353

using namespace std;

const ll N = 5e5 + 10, LG = 20;
ll n, dis[N], ps0[N][20], ps1[N][20], psr[N][20];
queue<ll> q;
bool mark[N];

int main() {
  fast_io;
  string x, y;
  cin >> n >> x >> y;
  ll a = 0, b = 0;
  for (int i = n - 1, j = 0; i >= 0; i--, j++)
    a += (x[i] == '1') * (1 << j); 
  for (int i = n - 1, j = 0; i >= 0; i--, j++)
    b += (y[i] == '1') * (1 << j);
  q.push(a);
  dis[a] = 0;
  mark[a] = true;
  if (a == b) kill(0);
  for (int mask = 0; mask < (1 << n); mask++) {
    for (int i = n - 1; i >= 0; i--) {
      ps0[mask][i] = ps0[mask][i + 1] + (!(mask & (1 << i))) * (1 << i);
      ps1[mask][i] = ps1[mask][i + 1] + (mask & (1 << i));
    }
  }
  while (q.size()) {
    int v = q.front();
    q.pop();
    for (int i = 0; i < n; i++) {
      for (int j = i; j < n; j++) {
        int x = v;
        x -= (ps1[v][i] - ps1[v][j + 1]);
        if (!mark[x]) {
          mark[x] = true;
          q.push(x);
          dis[x] = dis[v] + 1;
          if (x == b) goto Hell;
        }
        x = v;
        x += ps0[v][i] - ps0[v][j + 1];
        if (!mark[x]) {
          mark[x] = true;
          q.push(x);
          dis[x] = dis[v] + 1;
          if (x == b) goto Hell;
        }
        x = v;
        x += ps0[v][i] - ps0[v][j + 1];
        x -= (ps1[v][i] - ps1[v][j + 1]);
        if (!mark[x]) {
          mark[x] = true;
          q.push(x);
          dis[x] = dis[v] + 1;
          if (x == b) goto Hell;
        }
      }
    }
  }
  Hell:;
  cout << dis[b] << '\n';
  return 0; 
}

• Subtask 1: 6 / 6
• Subtask 2: 0 / 41
• Subtask 3: 0 / 4
• Subtask 4: 0 / 49