Determine if the Tuple is (\text{浴眼盯真})

A string quadruple \((a, b, c, d)\) is defined to be \(\text{浴眼盯真}\) if and only if all of the following conditions are satisfied:

• The first characters of both a and b are y.
• \(c = \texttt{ding}\).
• \(d = \texttt{zhen}\).

You are given four space-separated strings \(a\), \(b\), \(c\), and \(d\), all of which consist only of lowercase English letters. Determine whether the quadruple \((a, b, c, d)\) is \(\text{浴眼盯真}\). If it is, print Yes; otherwise, print No.

inputFormat

The input consists of a single line containing four space-separated strings \(a\), \(b\), \(c\), and \(d\).

outputFormat

Output a single line containing Yes if the quadruple \((a, b, c, d)\) is \(\text{浴眼盯真}\); otherwise, output No.

sample

yes yahoo ding zhen

Yes