Problem:
Score : 100 points

Problem Statement

You are given a three-digit positive integer N.

Determine whether N is a palindromic number.

Here, a palindromic number is an integer that reads the same backward as forward in decimal notation.

Constraints

100≤N≤999

N is an integer.

Input

Input is given from Standard Input in the following format:

N

Output

If N is a palindromic number, print Yes; otherwise, print No.

Sample Input 1

575

Sample Output 1

Yes

N=575 is also 575 when read backward, so it is a palindromic number. You should print Yes.

Sample Input 2

123

Sample Output 2

No

N=123 becomes 321 when read backward, so it is not a palindromic number. You should print No.

Sample Input 3

812

Sample Output 3

No

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

a, b, c, d = gets.chomp.split(' ').map(&:to_i)

if a < c
  if c < b
    if b < d
      print "#{b-c}"
    else
      print "#{d-c}"
    end
  else
    print '0'
  end
else
  if a < d
    print "#{d-a}"
  else
    print '0'
  end
end