# Find safe cells in a matrix

Given a matrix mat[][] containing the characters Z, P and * where Z is a zombie, P is a plant and * is a bare land. Given that a zombie can attack a plant if the plant is adjacent to the zombie (total 8 adjacent cells are possible). The task is to print the number of plants that are safe from the zombies.

Examples:

```Input:
mat[] = { "**P*",
"*Z**",
"*Z**",
"***P" }
Output: 1

Input:
mat[] = { "**P*P",
"*Z**",
"*P**",
"***P" }
Output: 2
```

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach: Traverse the matrix element by element, if the current element is a plant i.e. mat[i][j] = ‘P’ then check if the plant is surrounded by any zombie (in all the 8 adjacent cells). If the plant is safe then update count = count + 1. Print the count in the end.

Below is the implementation of the above approach:

## C++

 `// C++ implementation of the approach ` `#include ` `using` `namespace` `std; ` ` `  `// Function that returns true if mat[i][j] is a zombie ` `bool` `isZombie(``int` `i, ``int` `j, ``int` `r, ``int` `c, string mat[]) ` `{ ` `    ``if` `(i < 0 || j < 0 || i >= r || j >= c ` `        ``|| mat[i][j] != ``'Z'``) ` `        ``return` `false``; ` ` `  `    ``return` `true``; ` `} ` ` `  `// Function to return the count of plants ` `// that survived from the zombies attack ` `int` `Plant_Vs_Zombies(string mat[], ``int` `row, ``int` `col) ` `{ ` `    ``int` `i, j, count = 0; ` ` `  `    ``for` `(i = 0; i < row; i++) { ` `        ``for` `(j = 0; j < col; j++) { ` ` `  `            ``// If current cell is a plant ` `            ``if` `(mat[i][j] == ``'P'``) { ` ` `  `                ``// If current plant is safe from zombies ` `                ``if` `(!isZombie(i - 1, j - 1, row, col, mat) ` `                    ``&& !isZombie(i - 1, j, row, col, mat) ` `                    ``&& !isZombie(i - 1, j + 1, row, col, mat) ` `                    ``&& !isZombie(i, j - 1, row, col, mat) ` `                    ``&& !isZombie(i, j, row, col, mat) ` `                    ``&& !isZombie(i, j + 1, row, col, mat) ` `                    ``&& !isZombie(i + 1, j - 1, row, col, mat) ` `                    ``&& !isZombie(i + 1, j, row, col, mat) ` `                    ``&& !isZombie(i + 1, j + 1, row, col, mat)) { ` `                    ``count++; ` `                ``} ` `            ``} ` `        ``} ` `    ``} ` ` `  `    ``return` `count; ` `} ` ` `  `// Driver Code ` `int` `main() ` `{ ` `    ``// Input matrix ` `    ``string mat[] = { ``"**P*"``, ``"*Z**"``, ``"*Z**"``, ``"***P"` `}; ` ` `  `    ``// Rows and columns of the matrix ` `    ``int` `row = ``sizeof``(mat) / ``sizeof``(mat); ` `    ``int` `col = mat.length(); ` ` `  `    ``// Total plants survived ` `    ``cout << Plant_Vs_Zombies(mat, row, col); ` `} `

## Java

 `// Java implementation of the approach.  ` ` `  `class` `GfG ` `{ ` ` `  `    ``// Function that returns true if  ` `    ``// mat[i][j] is a zombie  ` `    ``static` `boolean` `isZombie(``int` `i, ``int` `j, ``int` `r, ` `                            ``int` `c, String mat[])  ` `    ``{  ` `        ``if` `(i < ``0` `|| j < ``0` `|| i >= r || j >= c  ` `            ``|| mat[i].charAt(j) != ``'Z'``)  ` `            ``return` `false``;  ` `     `  `        ``return` `true``;  ` `    ``}  ` `     `  `    ``// Function to return the count of plants  ` `    ``// that survived from the zombies attack  ` `    ``static` `int` `Plant_Vs_Zombies(String mat[],  ` `                            ``int` `row, ``int` `col)  ` `    ``{  ` `        ``int` `i, j, count = ``0``;  ` `     `  `        ``for` `(i = ``0``; i < row; i++)  ` `        ``{  ` `            ``for` `(j = ``0``; j < col; j++) ` `            ``{  ` `     `  `                ``// If current cell is a plant  ` `                ``if` `(mat[i].charAt(j) == ``'P'``)  ` `                ``{  ` `     `  `                    ``// If current plant is safe from zombies  ` `                    ``if` `(!isZombie(i - ``1``, j - ``1``, row, col, mat)  ` `                        ``&& !isZombie(i - ``1``, j, row, col, mat)  ` `                        ``&& !isZombie(i - ``1``, j + ``1``, row, col, mat)  ` `                        ``&& !isZombie(i, j - ``1``, row, col, mat)  ` `                        ``&& !isZombie(i, j, row, col, mat)  ` `                        ``&& !isZombie(i, j + ``1``, row, col, mat)  ` `                        ``&& !isZombie(i + ``1``, j - ``1``, row, col, mat)  ` `                        ``&& !isZombie(i + ``1``, j, row, col, mat)  ` `                        ``&& !isZombie(i + ``1``, j + ``1``, row, col, mat)) {  ` `                        ``count++;  ` `                    ``}  ` `                ``}  ` `            ``}  ` `        ``}  ` `        ``return` `count;  ` `    ``}  ` ` `  `    ``// Driver code ` `    ``public` `static` `void` `main(String []args) ` `    ``{ ` `         `  `        ``// Input matrix  ` `        ``String[] mat = { ``"**P*"``, ``"*Z**"``, ``"*Z**"``, ``"***P"` `};  ` `     `  `        ``// Rows and columns of the matrix  ` `        ``int` `row = mat.length;  ` `        ``int` `col = mat[``0``].length();  ` `     `  `        ``// Total plants survived  ` `        ``System.out.println(Plant_Vs_Zombies(mat, row, col)); ` `    ``} ` `} ` ` `  `// This code is contributed by Rituraj Jain `

## Python3

 `# Python3 implementation of the approach.  ` ` `  `# Function that returns true if  ` `# mat[i][j] is a zombie  ` `def` `isZombie(i, j, r, c, mat):  ` ` `  `    ``if` `(i < ``0` `or` `j < ``0` `or` `i >``=` `r ``or` `        ``j >``=` `c ``or` `mat[i][j] !``=` `'Z'``):  ` `        ``return` `True``;  ` ` `  `    ``return` `False``;  ` ` `  `# Function to return the count of plants  ` `# that survived from the zombies attack  ` `def` `Plant_Vs_Zombies(mat, row, col):  ` ` `  `    ``count ``=` `0``;  ` ` `  `    ``for` `i ``in` `range``(row):  ` `        ``for` `j ``in` `range``(col): ` ` `  `            ``# If current cell is a plant  ` `            ``if` `(mat[i][j] ``=``=` `'P'``): ` ` `  `                ``# If current plant is safe from zombies  ` `                ``if` `(isZombie(i ``-` `1``, j ``-` `1``, row, col, mat) ``and` `                    ``isZombie(i ``-` `1``, j, row, col, mat) ``and`  `                    ``isZombie(i ``-` `1``, j ``+` `1``, row, col, mat) ``and`  `                    ``isZombie(i, j ``-` `1``, row, col, mat) ``and`  `                    ``isZombie(i, j, row, col, mat) ``and`  `                    ``isZombie(i, j ``+` `1``, row, col, mat) ``and`  `                    ``isZombie(i ``+` `1``, j ``-` `1``, row, col, mat) ``and`  `                    ``isZombie(i ``+` `1``, j, row, col, mat) ``and`  `                    ``isZombie(i ``+` `1``, j ``+` `1``, row, col, mat)): ` `                    ``count ``+``=` `1``;  ` `    ``return` `count;  ` ` `  `# Driver code ` ` `  `# Input matrix  ` `mat ``=` `[``"**P*"``, ``"*Z**"``, ``"*Z**"``, ``"***P"``];  ` ` `  `# Rows and columns of the matrix  ` `row ``=` `len``(mat);  ` `col ``=` `len``(mat[``0``]);  ` ` `  `# Total plants survived  ` `print``(Plant_Vs_Zombies(mat, row, col)); ` ` `  `# This code is contributed by mits `

## C#

 `// C# implementation of the approach. ` `using` `System; ` ` `  `class` `GfG ` `{ ` ` `  `    ``// Function that returns true if  ` `    ``// mat[i][j] is a zombie  ` `    ``static` `bool` `isZombie(``int` `i, ``int` `j, ``int` `r, ` `                            ``int` `c, String []mat)  ` `    ``{  ` `        ``if` `(i < 0 || j < 0 || i >= r || j >= c  ` `            ``|| mat[i][j] != ``'Z'``)  ` `            ``return` `false``;  ` `     `  `        ``return` `true``;  ` `    ``}  ` `     `  `    ``// Function to return the count of plants  ` `    ``// that survived from the zombies attack  ` `    ``static` `int` `Plant_Vs_Zombies(String []mat,  ` `                            ``int` `row, ``int` `col)  ` `    ``{  ` `        ``int` `i, j, count = 0;  ` `     `  `        ``for` `(i = 0; i < row; i++)  ` `        ``{  ` `            ``for` `(j = 0; j < col; j++) ` `            ``{  ` `     `  `                ``// If current cell is a plant  ` `                ``if` `(mat[i][j] == ``'P'``)  ` `                ``{  ` `     `  `                    ``// If current plant is safe from zombies  ` `                    ``if` `(!isZombie(i - 1, j - 1, row, col, mat)  ` `                        ``&& !isZombie(i - 1, j, row, col, mat)  ` `                        ``&& !isZombie(i - 1, j + 1, row, col, mat)  ` `                        ``&& !isZombie(i, j - 1, row, col, mat)  ` `                        ``&& !isZombie(i, j, row, col, mat)  ` `                        ``&& !isZombie(i, j + 1, row, col, mat)  ` `                        ``&& !isZombie(i + 1, j - 1, row, col, mat)  ` `                        ``&& !isZombie(i + 1, j, row, col, mat)  ` `                        ``&& !isZombie(i + 1, j + 1, row, col, mat))  ` `                    ``{  ` `                        ``count++;  ` `                    ``}  ` `                ``}  ` `            ``}  ` `        ``}  ` `        ``return` `count;  ` `    ``}  ` ` `  `    ``// Driver code ` `    ``public` `static` `void` `Main(String []args) ` `    ``{ ` `         `  `        ``// Input matrix  ` `        ``String[] mat = { ``"**P*"``, ``"*Z**"``, ``"*Z**"``, ``"***P"` `};  ` `     `  `        ``// Rows and columns of the matrix  ` `        ``int` `row = mat.Length;  ` `        ``int` `col = mat.Length;  ` `     `  `        ``// Total plants survived  ` `        ``Console.WriteLine(Plant_Vs_Zombies(mat, row, col)); ` `    ``} ` `} ` ` `  `// This code contributed by Rajput-Ji `

## PHP

 `= ``\$r` `||  ` `        ``\$j` `>= ``\$c` `|| ``\$mat``[``\$i``][``\$j``] != ``'Z'``)  ` `        ``return` `false;  ` ` `  `    ``return` `true;  ` `}  ` ` `  `// Function to return the count of plants  ` `// that survived from the zombies attack  ` `function` `Plant_Vs_Zombies(``\$mat``, ``\$row``, ``\$col``)  ` `{  ` `    ``\$i``; ``\$j``; ``\$count` `= 0;  ` ` `  `    ``for` `(``\$i` `= 0; ``\$i` `< ``\$row``; ``\$i``++)  ` `    ``{  ` `        ``for` `(``\$j` `= 0; ``\$j` `< ``\$col``; ``\$j``++) ` `        ``{  ` ` `  `            ``// If current cell is a plant  ` `            ``if` `(``\$mat``[``\$i``][``\$j``] == ``'P'``)  ` `            ``{  ` ` `  `                ``// If current plant is safe from zombies  ` `                ``if` `(!isZombie(``\$i` `- 1, ``\$j` `- 1, ``\$row``, ``\$col``, ``\$mat``) && ` `                    ``!isZombie(``\$i` `- 1, ``\$j``, ``\$row``, ``\$col``, ``\$mat``) && ` `                    ``!isZombie(``\$i` `- 1, ``\$j` `+ 1, ``\$row``, ``\$col``, ``\$mat``) &&  ` `                    ``!isZombie(``\$i``, ``\$j` `- 1, ``\$row``, ``\$col``, ``\$mat``) &&  ` `                    ``!isZombie(``\$i``, ``\$j``, ``\$row``, ``\$col``, ``\$mat``) && ` `                    ``!isZombie(``\$i``, ``\$j` `+ 1, ``\$row``, ``\$col``, ``\$mat``) && ` `                    ``!isZombie(``\$i` `+ 1, ``\$j` `- 1, ``\$row``, ``\$col``, ``\$mat``) && ` `                    ``!isZombie(``\$i` `+ 1, ``\$j``, ``\$row``, ``\$col``, ``\$mat``) &&  ` `                    ``!isZombie(``\$i` `+ 1, ``\$j` `+ 1, ``\$row``, ``\$col``, ``\$mat``))  ` `                ``{  ` `                    ``\$count``++;  ` `                ``}  ` `            ``}  ` `        ``}  ` `    ``}  ` `    ``return` `\$count``;  ` `}  ` ` `  `// Driver code ` ` `  `// Input matrix  ` `\$mat` `= ``array``( ``"**P*"``, ``"*Z**"``, ``"*Z**"``, ``"***P"` `);  ` ` `  `// Rows and columns of the matrix  ` `\$row` `= sizeof(``\$mat``);  ` `\$col` `= ``strlen``(``\$mat``);  ` ` `  `// Total plants survived  ` `echo``(Plant_Vs_Zombies(``\$mat``, ``\$row``, ``\$col``)); ` ` `  `// This code is contributed by Code_Mech. ` `?> `

Output:

```1
```

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