Problem:
Score : 100 points

Problem Statement

Given is a string S representing the day of the week today.

S is SUN, MON, TUE, WED, THU, FRI, or SAT, for Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, and Saturday, respectively.

After how many days is the next Sunday (tomorrow or later)?

Constraints

S is SUN, MON, TUE, WED, THU, FRI, or SAT.

Input

Input is given from Standard Input in the following format:

S

Output

Print the number of days before the next Sunday.

Sample Input 1

SAT

Sample Output 1

1

It is Saturday today, and tomorrow will be Sunday.

Sample Input 2

SUN

Sample Output 2

7

It is Sunday today, and seven days later, it will be Sunday again.

Solution in Ruby (2.3.3) (judge verdict: Runtime Error)

num = gets.chomp.to_i
letters = gets.chomp.split('')
$a_to_z = [*"A".."Z"]
$answer = []
letters.each do |letter|
  if $a_to_z.index(letter) + $num < $a_to_z.count
    $answer << $a_to_z[$a_to_z.index(letter) + $num]
  else
    $answer << $a_to_z[($a_to_z.index(letter) + $num) - $a_to_z.count]
  end 
end
puts $answer.join("")