Problems

# Parallelogram

# Parallelogram

**4** numbers **a, b, c, d**, defining lengths of pieces are set. Define, is it possible to form a parallelogram from these pieces.

**Input**

In a unique line set 4 numbers through a blank.

**Output**

Deduce in a unique line a word **"YES"** if it is possible to form a parallelogram or **"NO"** (without inverted commas) otherwise.

Input example #1

2 4 2 4

Output example #1

YES