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Minesweeper Neighbor Counts

Annotate a rectangular board.

Problem

Annotate a rectangular board. A star (*) is a mine and a dot (.) is a safe cell. For each safe cell, count mines in the eight surrounding cells, including diagonals. Replace it with the count from 1 to 8, or keep a dot if the count is zero. Preserve every mine. Cells outside the board do not exist.

Implement minesweeper_neighbor_counts(board).

Input

board: The rows from top to bottom; characters run left to right.

Output

Return the annotated rows in the same order and dimensions.

Constraints

1 ≤ rows, columns ≤ 200. Every row has the same nonzero length and contains only * and . .

Examples

Example 1
Input:
board = ["*..", "...", "..*"]

Expected output:
expected = ["*1.", "121", ".1*"]
Input:
std::vector<std::string> board = {"*..", "...", "..*"};

Expected output:
std::vector<std::string> expected = {"*1.", "121", ".1*"};
Input:
string[] board = new string[] {"*..", "...", "..*"};

Expected output:
string[] expected = new string[] {"*1.", "121", ".1*"};

Explanation

The center touches both mines, so its count is 2. The top-right and bottom-left touch none and stay dots. Other safe cells touch one mine.

Example 2
Input:
board = ["..."]

Expected output:
expected = ["..."]
Input:
std::vector<std::string> board = {"..."};

Expected output:
std::vector<std::string> expected = {"..."};
Input:
string[] board = new string[] {"..."};

Expected output:
string[] expected = new string[] {"..."};

Explanation

This one-row board has no mines. All counts are zero, so every dot remains a dot.

References

This challenge is adapted for CodeUtility. Follow the statement and constraints above.

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