How to input integer value to an array, based preceeding row + column values? [duplicate]

Answer 1

Your homework, sir.

puts 'Please input: '
x = gets.chomp

col = []
row = []
sign = ''
val = ''

x.chars.each_slice(2) do |u|
  case u[0]
  when 'R' then
    row << u[1]
  when 'C' then
    col << u[1]
  when '+', '-'
    sign, val = u[0], u[1]
  else
    puts 'Invalid input.'
    exit
  end
end

big_row = row.max.to_i
big_col = col.max.to_i
table = Array.new (big_row) { Array.new(big_col) }

# Initialize table to all zeros
table.map! do |row|
  row.map! { |col| 0 }
end

rows_range = row.length == 1 ? row[0]..row[0] : row[0]..row[1]
cols_range = col.length == 1 ? col[0]..col[0] : col[0]..col[1]

table.each_with_index do |row, ri|
  if rows_range.include? (ri + 1).to_s
    row.each_with_index do |col, ci|
      if cols_range.include? (ci + 1).to_s
        table[ri][ci] = (sign + val).to_i
      end
    end
  end
end

# Padding for fields in table.
padding = 4

# Table
table.each do |row|
  row.each do |col|
    print "#{col.to_s.rjust(padding)}"
  end
  print "\n"
end