# Shortest path on a Square

Given side of a square n and two points (x1, y1) and (x2, y2) on the boundaries of the given square. The task is to find the shortest path through the square sides between these two points where the corner coordinates of the square are are (0, 0), (n, 0), (0, n) and (n, n) .

Examples:

Input: n = 2, x1 = 0, y1 = 0, x2 = 1, y2 = 0
Output: 1

Input: n = 26, x1 = 21, y1 = 0, x2 = 26, y2 = 14
Output: 19

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

Approach:

• If both the x and y coordinates of a point is greater than the other and the points are not on opposite sides of square then the shortest distance will be abs(x2 – x1) + abs(y2 – y1).
• Else, the shortest distance will be equal to min((x1 + y1 + x2 + y2), (4 * n) – (x1 + y1 + x2 + y2))

Below is the implementation of the above approach:

## C++

 `// C++ implementation of the approach ` `#include ` `using` `namespace` `std; ` ` `  `// Function to return the length ` `// of the minimum path between ` `// two points on a square of given side ` `int` `minPath(``int` `n, ``int` `x1, ``int` `y1, ``int` `x2, ``int` `y2) ` `{ ` ` `  `    ``// If both of the x and y coordinates ` `    ``// of one point is greater than the other ` `    ``if` `((x1 <= x2 && y1 <= y2) || (x1 >= x2 && y1 >= y2)) ` `    ``{ ` `        ``// If the points are not on opposite sides ` `        ``if` `(!(``abs``(y2 - y1) == n || ``abs``(x2 - x1) == n)) ` `            ``return` `(``abs``(x1 - x2) + ``abs``(y1 - y2)); ` `    ``} ` `    ``return` `min(x1 + x2 + y1 + y2, (4 * n) - (x1 + x2 + y1 + y2)); ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` `    ``// Side of the square ` `    ``int` `n = 4; ` `    ``int` `x1 = 2, y1 = 0, x2 = 3, y2 = 4; ` `    ``cout << minPath(n, x1, y1, x2, y2); ` ` `  `    ``return` `0; ` `} ` ` `  `// improved by Sonal Agrawal `

## Python 3

 `# Python3 implementation of above approach ` ` `  `# Function to return the length of the  ` `# minimum path between two points ` `# on a square of given side  ` `def` `minPath(n, x1, y1, x2, y2): ` ` `  `    ``# If both of the x and y coordinates  ` `    ``# of one point is greater than the other  ` `    ``if` `((x1 <``=` `x2 ``and` `y1 <``=` `y2) ``or`  `        ``(x1 >``=` `x2 ``and` `y1 >``=` `y2)) ``and` `        ``not` `(``abs``(y2 ``-` `y1) ``=``=` `n ``or` `abs``(x2 ``-` `x1) ``=``=` `n):  ` `        ``return` `(``abs``(x1 ``-` `x2) ``+` `abs``(y1 ``-` `y2));  ` ` `  `    ``return` `min``(x1 ``+` `x2 ``+` `y1 ``+` `y2, (``4` `*` `n) ``-`  `              ``(x1 ``+` `x2 ``+` `y1 ``+` `y2));  ` ` `  `# Driver code  ` ` `  `# side of the square ` `n ``=` `4``; x1 ``=` `2``; y1 ``=` `0` `x2 ``=` `3``; y2 ``=` `4` `print``(minPath(n, x1, y1, x2, y2)) ` ` `  `# This code is contributed  ` `# by Shashank_Sharma `

## C#

 `// C# implementation of the approach ` `using` `System; ` ` `  `class` `GFG ` `{ ` `     `  `// Function to return the length ` `// of the minimum path between ` `// two points on a square of given side ` `static` `int` `minPath(``int` `n, ``int` `x1, ``int` `y1,  ` `                        ``int` `x2, ``int` `y2) ` `{ ` ` `  `    ``// If both of the x and y coordinates ` `    ``// of one point is greater than the other ` `    ``if` `((x1 <= x2 && y1 <= y2) || (x1 >= x2 && y1 >= y2)) ` `    ``{ ` `        ``// If the points are not on opposite sides ` `        ``if` `(!(Math.Abs(y2 - y1) == n || Math.Abs(x2 - x1) == n)) ` `            ``return` `(Math.Abs(x1 - x2) + Math.Abs(y1 - y2)); ` `    ``} ` `    ``return` `Math.Min(x1 + x2 + y1 + y2, (4 * n) - (x1 + x2 + y1 + y2)); ` `} ` ` `  `// Driver code ` `public` `static` `void` `Main() ` `{ ` `    ``// Side of the square ` `    ``int` `n = 4; ` `    ``int` `x1 = 2, y1 = 0, x2 = 3, y2 = 4; ` `    ``Console.Write(minPath(n, x1, y1, x2, y2)); ` `} ` `} ` ` `  `// This code is contributed  ` `// by Akanksha Rai `

## PHP

 `= ``\$x2` `&& ``\$y1` `>= ``\$y2``)) ` `    ``{ ` `        ``// If the points are not on opposite sides ` `        ``if` `(!(``abs``(``\$y2` `- ``\$y1``) == ``\$n` `|| ``abs``(``\$x2` `- ``\$x1``) == ``\$n``)) ` `            ``return` `(``abs``(``\$x1` `- ``\$x2``) + ``abs``(``\$y1` `- ``\$y2``)); ` `    ``} ` `    ``return` `min(``\$x1` `+ ``\$x2` `+ ``\$y1` `+ ``\$y2``, (4 * ``\$n``) - (``\$x1` `+ ``\$x2` `+ ``\$y1` `+ ``\$y2``)); ` `     `  `}  ` ` `  `// Driver code  ` ` `  `// Side of the square  ` `\$n` `= 4;  ` `\$x1` `= 2 ; ` `\$y1` `= 0 ; ` `\$x2` `= 3 ; ` `\$y2` `= 4 ;  ` `echo` `minPath(``\$n``, ``\$x1``, ``\$y1``, ``\$x2``, ``\$y2``);  ` `     `  `// This code is contributed by Ryuga ` `?> `

Output:

```1
```

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