Submission #408880

#	Time	Username	Problem	Language	Result	Execution time	Memory
408880		MilosMilutinovic	The Kingdom of JOIOI (JOI17_joioi)	C++14	100 / 100	1231 ms	19472 KiB

joioi

#include <bits/stdc++.h>

using namespace std;

const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, m;
  cin >> n >> m;
  vector<vector<int>> a(n, vector<int>(m));
  int mn = 1e9, mx = 0;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      cin >> a[i][j];
      mn = min(mn, a[i][j]);
      mx = max(mx, a[i][j]);
    }
  }
  auto Can = [&](int dif) {
    int col = 1e9;
    for (int i = 0; i < n; i++) {
      for (int j = 0; j < m; j++) {
        if (a[i][j] < mx - dif) {
          col = min(col, j);
        }
      }
      for (int j = 0; j < m; j++) {
        if (a[i][j] > mn + dif && j >= col) {
          return false;
        }
      }
    }
    return true;
  };
  int ans = 1e9;
  function<void()> Do = [&]() {
    int bot = 0, top = 1e9;
    while (bot <= top) {
      int mid = bot + top >> 1;
      if (Can(mid)) {
        ans = min(ans, mid);
        top = mid - 1;
      } else {
        bot = mid + 1;
      }
    }
  };
  Do();
  reverse(a.begin(), a.end());
  Do();
  for (int i = 0; i < n; i++) reverse(a[i].begin(), a[i].end());
  Do();
  reverse(a.begin(), a.end());
  Do();
  cout << ans << '\n';
  return 0;
}

Compilation message (stderr)

joioi.cpp: In lambda function:
joioi.cpp:42:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   42 |       int mid = bot + top >> 1;
      |                 ~~~~^~~~~

• Subtask 1: 15 / 15
• Subtask 2: 45 / 45
• Subtask 3: 40 / 40