In this challenge, you have to establish if a given integer n is a Sastry number. If the number resulting from the concatenation of an integer n with its successor is a perfect square, then n is a Sastry Number.

Given a positive integer n, implement a function that returns true if n is a Sastry number, or false if it's not.

Examples

is_sastry(183) ➞ true
# Concatenation of n and its successor = 183184
# 183184 is a perfect square (428 ^ 2)

is_sastry(184) ➞ false
# Concatenation of n and its successor = 184185
# 184185 is not a perfect square

is_sastry(106755) ➞ true
# Concatenation of n and its successor = 106755106756
# 106755106756 is a perfect square (326734 ^ 2)

Notes

• A perfect square is a number with a square root equals to a whole integer.
• You can expect only valid positive integers greater than 0 as input, without exceptions to handle. Zero is a perfect square, but the concatenation 00 isn't considered as a valid result to check.