Spreading Ink Blot

Medium

In the first minute a blot of ink lands on an infinite sheet of grid paper and colours one cell. Every following minute the ink spreads: every clean cell that shares a **side** with an inked cell gets inked too. Return how many cells are inked after minutes minutes.

Example 1

minutes=3 → 13

After the first minute there is 1 cell, the second adds its 4 neighbours, the third adds 8 more. That is 13 cells forming a diamond.

Example 2

minutes=1 → 1

Only the starting cell has been inked.

Example 3

minutes=6 → 61

Constraints

1 ≤ minutes ≤ 10⁵

Have you seen this problem in a real interview?

Solved by0

Tried by0

Submissions0

Acceptance—

Topics

Math

Similar problems

Adding Digit Lists Medium Backwards Digits in 32 Bits Medium Number in Roman Numerals Medium Division Without Dividing Medium Multiplying Digit Strings Medium

Input

minutes=3

Expected

Run checks the first 3 tests in your browser. Submit checks all 40 tests on the server, hidden ones included.