Олимпиадный тренинг

Задача 20378. Elephant


It is required to determine whether the bishop, standing on a cell with the specified coordinates (row number and column number), beats a piece, standing on another specified cell.

Input

Four numbers are entered: the coordinates of the elephant and the coordinates of another figure. Coordinates are integers between 1 and 8.

Output

It is required to print the word YES if the bishop is able to capture the piece in 1 move, otherwise print the word NO

Examples
input
1
1
5
5
output
YES

input
3
2
2
2
output
NO