P1451 Count the Number of Cells

A rectangular array consists of digits $0$ to $9$. Digits $1$ to $9$ denote cells. Two positions belong to the same cell if, moving up, down, left, or right through positions with cell digits, they are connected. Given the array, count the number of cells.

The first line contains two integers $n$ and $m$. The next $n$ lines each contain a string of length $m$ consisting only of characters `0` to `9`, representing the $n \times m$ matrix.

Output a single integer, the number of cells.

Constraints For $100\%$ of the testdata, $1 \le n, m \le 100$. Translated by ChatGPT 5