Matrix Row Means

Return list of mean of each row in a 2D matrix.

Your task

Implement this function:

def row_means(matrix: list) -> list:

Write the function only — the arguments are read for you and the return value is printed automatically.

Arguments arrive as one Python literal per line, in this order: matrix.

Example

Input

[[1, 2], [3, 4]]

Output

[1.5, 3.5]