Introduction

AtCoder Problems * Use Recommendations to solve past problems. Thanks to AtCoder and AtCoder Problems.

This theme

AtCoder Beginner Contest 107 B - Grid Compression Difficulty: 434

This theme, string manipulation Ruby

`ruby.rb`


h, w = gets.split.map(&:to_i)
a = []
h.times do |i|
  s = gets.chomp
  a.push(s) if s.index('#')
end
(w - 1).downto(0) do |i|
  if a.all?{|x| x[i] == '.'}
    a.each do |x|
      x[i] = ''
    end
  end
end
puts a

`count.rb`


  a.push(s) if s.count('.') != w
  a.push(s) if s.index('#')
  a.push(s) if s.contain?('#')

The count method, ʻindex method, contain` method, and other regular expressions are also OK.

`index.rb`


      x[i] = ''

For * Ruby *, you can directly replace the characters specified in the index. ** Addition ** I reviewed the code from the comments I received. Python

`python.py`


h, w = map(int, input().split())
a = []
for i in range(h):
    s = input()
    if s.count('.') != w:
        a.append(s)
b = []
for i in range(w):
    f = True
    for x in a:
        if x[i] != '.':
            f = False
    if f:
        b.append(i)
for x in a:
    for i in range(len(x)):
        f = True
        for j in b:
            if i == j:
                f = False
        if f:
            print(x[i], end='')
    print()

`find.py`


    if s.count('.') != w:
    if s.find('#') == -1:

You can also use the find method.

Python * cannot be replaced or deleted at the character position, so the deleted position is saved and skipped at the time of output. Perl

`perl.pl`


chomp (my ($h, $w) = split / /, <STDIN>);
my @a;
for my $i (1..$h) {
  chomp (my $s = <STDIN>);
  if (scalar(grep {$_ eq '.'} (split '', $s)) != $w) {
    push @a, $s;
  }
}
for my $i (1..$w) {
  my $f = 1;
  for my $x (@a) {
    $f = 0 if substr($x, $w - $i, 1) ne '.';
  }
  if ($f) {
    for my $x (@a) {
      substr($x, $w - $i, 1) = '';
    }
  }
}
for my $x (@a) {
  print "$x\n";
}

`grep.pl`


  if (scalar(grep {$_ eq '.'} (split '', $s)) != $w) {
  if (index($s, '#') == -1) {

ʻIndex` is also OK. Java

`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());
        List<String> a = new ArrayList<>();
        for (int i = 0; i < h; i++) {
            String s = sc.next();
            if (s.contains("#")) {
                a.add(s);
            }
        }
        sc.close();
        List<Integer> b = new ArrayList<>();
        for (int i = 0; i < w; i++) {
            boolean f = false;
            for (String x : a) {
                if (x.charAt(i) == '#') {
                    f = true;
                    break;
                }
            }
            if (f) {
                b.add(i);
            }
        }
        for (String x : a) {
            for (int i = 0; i < w; i++) {
                if (b.contains(i))
                    System.out.print(x.charAt(i));
            }
            System.out.println();
        }
    }
}

`contains.java`


            if (s.contains("#")) {

There seems to be no easy way to count the number of ., so I'm using the contains method. ** Addition ** From the comment section, I got the idea of split with .. Also, I received a comment that charAt is better than substring, so I modified the code.