array.rb

cm = Array.new(h + 2){Array.new(w + 2, 0)}

When checking up, down, left and right, the array is enlarged so that you do not get an error with nil.

push.rb

h, w = gets.split.map(&:to_i)
cm = Array.new(h + 2){Array.new(w + 2, 0)}
que = []
1.upto(h) do |i|
  s = gets.chomp
  1.upto(w) do |j|
    if s[j - 1] == '.'
      cm[i][j] = -1
    else
      que << i << j
      cm[i][j] = 0
    end
  end
end
ans = 0
while que.size > 0
  y = que.shift
  x = que.shift
  ans = cm[y][x] + 1
  if cm[y + 1][x] == -1
    cm[y + 1][x] = ans
    que << y + 1 << x
  end
  if cm[y - 1][x] == -1
    cm[y - 1][x] = ans
    que << y - 1 << x
  end
  if cm[y][x + 1] == -1
    cm[y][x + 1] = ans
    que << y << x + 1
  end
  if cm[y][x - 1] == -1
    cm[y][x - 1] = ans
    que << y << x - 1
  end
end
puts ans - 1

Code that uses << instead of the push you received in the comments. Here, the execution time is shortened. Python

• Python * was TLE this time. Looking at the answers of other athletes, there are many examples of using numpy.

cmd.exe

C:\Users\user>pacman -S mingw-w64-x86_64-python-numpy

I installed it immediately.

** Addition ** I passed by PyPy.

PyPy.py

from collections import deque

h, w = map(int, input().split())
cm = [[0 for j in range(w + 2)] for i in range(h + 2)]
que = deque([])
for i in range(1, h + 1):
    s = input()
    for j in range(1, w + 1):
        if s[j - 1] == ".":
            cm[i][j] = -1
        else:
            que.append(i)
            que.append(j)
ans = 0
while len(que) > 0:
    y = que.popleft()
    x = que.popleft()
    ans = cm[y][x] + 1
    if cm[y + 1][x] == -1:
        cm[y + 1][x] = ans
        que.append(y + 1)
        que.append(x)
    if cm[y - 1][x] == -1:
        cm[y - 1][x] = ans
        que.append(y - 1)
        que.append(x)
    if cm[y][x + 1] == -1:
        cm[y][x + 1] = ans
        que.append(y)
        que.append(x + 1)
    if cm[y][x - 1] == -1:
        cm[y][x - 1] = ans
        que.append(y)
        que.append(x - 1)
print(ans - 1)

Perl

• Perl * was TLE this time. Looking at the answers of other athletes. .. .. There is no correct answer.

Java This time it is a double stand. The first is a copy of * previous code * with some modifications.

java.java

import java.util.*;

class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int h = Integer.parseInt(sc.next());
        int w = Integer.parseInt(sc.next());
        int cm[][] = new int[h + 2][w + 2];
        Deque<Integer> que = new ArrayDeque<>();
        for (int i = 1; i <= h; i++) {
            String s = sc.next();
            for (int j = 1; j <= w; j++) {
                if (".".equals(s.substring(j - 1, j))) {
                    cm[i][j] = -1;
                } else {
                    que.add(i);
                    que.add(j);
                }
            }
        }
        sc.close();
        int ans = 0;
        while (que.size() > 0) {
            int y = que.poll();
            int x = que.poll();
            ans = cm[y][x] + 1;
            if (cm[y + 1][x] == -1) {
                cm[y + 1][x] = ans;
                que.add(y + 1);
                que.add(x);
            }
            if (cm[y - 1][x] == -1) {
                cm[y - 1][x] = ans;
                que.add(y - 1);
                que.add(x);
            }
            if (cm[y][x + 1] == -1) {
                cm[y][x + 1] = ans;
                que.add(y);
                que.add(x + 1);
            }
            if (cm[y][x - 1] == -1) {
                cm[y][x - 1] = ans;
                que.add(y);
                que.add(x - 1);
            }
        }
        System.out.println(ans - 1);
    }
}

array.java

        int cm[][] = new int[h + 2][w + 2];

When checking up, down, left and right, the array is enlarged so as not to get ʻArrayIndexOutOfBoundsException`.

class.java

import java.util.*;

class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int h = Integer.parseInt(sc.next());
        int w = Integer.parseInt(sc.next());
        int s[][] = new int[h + 2][w + 2];
        Queue<Pair> que = new ArrayDeque<>();
        for (int i = 1; i <= h; i++) {
            char c[] = sc.next().toCharArray();
            for (int j = 1; j <= w; j++) {
                if (c[j - 1] == '.') {
                    s[i][j] = -1;
                } else {
                    que.add(new Pair(i, j));
                }

            }
        }
        sc.close();

        Pair p;
        int ans = 0;
        while (!que.isEmpty()) {
            p = que.poll();
            ans = s[p.x][p.y] + 1;
            if (s[p.x + 1][p.y] == -1) {
                s[p.x + 1][p.y] = ans;
                que.add(new Pair(p.x + 1, p.y));
            }
            if (s[p.x - 1][p.y] == -1) {
                s[p.x - 1][p.y] = ans;
                que.add(new Pair(p.x - 1, p.y));
            }
            if (s[p.x][p.y + 1] == -1) {
                s[p.x][p.y + 1] = ans;
                que.add(new Pair(p.x, p.y + 1));
            }
            if (s[p.x][p.y - 1] == -1) {
                s[p.x][p.y - 1] = ans;
                que.add(new Pair(p.x, p.y - 1));
            }
        }
        System.out.println(ans - 1);
    }
}

class Pair {
    int x;
    int y;

    public Pair(int x, int y) {
        this.x = x;
        this.y = y;
    }
}

ArrayDeque seems to be slow, so in order to reduce inflows and outflows, classes are generated and passed for each class.

• Java * was a child who could do it.

Summary

• Solved AGC 033 A
• Become familiar with Ruby
• Installed numpy
• Java was a capable child

Referenced site

• How to use numpy *
• Solving with Ruby, Perl, Java and Python AtCoder ATC 002 A *