Given a N * N matrix and the task is to check matrix is idempotent matrix or not.

See the sample input.

Idempotent matrix M follows the following property :

M*M = M

Input format :

Line 1 : Size N of the matrix
Line 2 to N + 1 : NXN elements of the matrix

Output Format :

 true or false

Constraints :

 1 <= N <= 10^3