#2579
Count Total Number of Colored Cells
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Description
On an infinite 2D grid, at minute 1 you color one cell blue. Each subsequent minute, every uncolored cell sharing an edge with a blue cell also turns blue. Return the total number of blue cells after n minutes.
Example 1:
Input: n = 1
Output: 1
Explanation: After 1 minute, there is only 1 blue cell, so we return 1.
Example 2:
Input: n = 2
Output: 5
Explanation: After 2 minutes, there are 4 colored cells on the boundary and 1 in the center, so we return 5.
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