Submission #958384

#	Time	Username	Problem	Language	Result	Execution time	Memory
958384		Soumya1	Abduction 2 (JOI17_abduction2)	C++17	44 / 100	87 ms	18516 KiB

abduction2

#include <bits/stdc++.h>
using namespace std;
const int mxN = 5e4 + 5;
const int lg = 16;
int a[mxN][lg], b[mxN][lg];
map<int, int> dp;
int n, m, q;
int solve(int x, int y, int dir) {
  if (x <= 0 || y <= 0 || x > n || y > m) return -1;
  int node = (x * (m + 1) + y) * 2 + dir;
  if (dp.find(node) != dp.end()) return dp[node];
  int ans = 0;
  if (dir == 0) {
    int ry = y + 1, ly = y - 1;
    for (int i = lg - 1; i >= 0; i--) {
      if (ry + (1 << i) - 1 <= m && b[ry][i] <= a[x][0]) ry += (1 << i);
      if (ly - (1 << i) + 1 >= 1 && b[ly - (1 << i) + 1][i] <= a[x][0]) ly -= (1 << i);
    }
    ans = max(ans, solve(x, ry, 1) + ry - y);
    ans = max(ans, solve(x, ly, 1) + y - ly);
  } else {
    int rx = x + 1, lx = x - 1;
    for (int i = lg - 1; i >= 0; i--) {
      if (rx + (1 << i) - 1 <= n && a[rx][i] <= b[y][0]) rx += (1 << i);
      if (lx - (1 << i) + 1 >= 1 && a[lx - (1 << i) + 1][i] <= b[y][0]) lx -= (1 << i);
    }
    ans = max(ans, solve(rx, y, 0) + rx - x);
    ans = max(ans, solve(lx, y, 0) + x - lx);
  }

  return dp[node] = ans;
}
void testCase() {
  cin >> n >> m >> q;
  for (int i = 1; i <= n; i++) cin >> a[i][0];
  for (int i = 1; i <= m; i++) cin >> b[i][0];
  for (int j = 1; j < lg; j++) {
    for (int i = 1; i + (1 << j) - 1 <= n; i++) {
      a[i][j] = max(a[i][j - 1], a[i + (1 << (j - 1))][j - 1]);
    }
  }
  for (int j = 1; j < lg; j++) {
    for (int i = 1; i + (1 << j) - 1 <= m; i++) {
      b[i][j] = max(b[i][j - 1], b[i + (1 << (j - 1))][j - 1]);
    }
  }
  while (q--) {
    int x, y;
    cin >> x >> y;
    cout << max(solve(x, y, 0), solve(x, y, 1)) << "\n";
  }
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  testCase();
  return 0;
}

• Subtask 1: 13 / 13
• Subtask 2: 10 / 10
• Subtask 3: 17 / 17
• Subtask 4: 4 / 4
• Subtask 5: 0 / 56