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#2579 - Count Total Number of Colored Cells
Problem Description
There exists an infinitely large two-dimensional grid of uncolored unit cells.
You are given a positive integer n, indicating that you must do the following routine for n minutes:
- At the first minute, color any arbitrary unit cell blue.
- Every minute thereafter, color blue every uncolored cell that touches a blue cell.
Below is a pictorial representation of the state of the grid after minutes 1, 2, and 3.
Solution
/**
* @param {number} n
* @return {number}
*/
var coloredCells = function(n) {
return 1 + 2 * n * (n - 1);
};