# Strobogrammatic number

For the given length n, find all n-length Strobogrammatic numbers.

Strobogrammatic Number is a number whose numeral is rotationally symmetric so that it appears the same when rotated 180 degrees. In other words, Strobogrammatic Number appears the same right-side up and upside down.

0 after 180° rotation : (0 → 0)
1 after 180° rotation : (1 → 1)
8 after 180° rotation : (8 → 8)
6 after 180° rotation : (6 → 9)
9 after 180° rotation : (9 → 6)

Examples :

```Input : n = 2
Output : 88  11  96  69

Input : n = 4
Output : 8008 1001 9006 6009 8888 1881 9886 6889 8118 1111
9116 6119 8968 1961 9966 6969 8698 1691 9696 6699
```

Below is the Python3 implementation :

 `# Python program to print all ` `# Strobogrammatic number of length n ` ` `  `# strobogrammatic function  ` `def` `strobogrammatic_num(n): ` `     `  `    ``result ``=` `numdef(n, n) ` `    ``return` `result ` `     `  `# definition function ` `def` `numdef(n, length): ` `     `  `    ``if` `n ``=``=` `0``: ``return` `[""] ` `    ``if` `n ``=``=` `1``: ``return` `[``"1"``, ``"0"``, ``"8"``] ` `     `  `    ``middles ``=` `numdef(n ``-` `2``, length) ` `    ``result ``=` `[] ` `     `  `    ``for` `middle ``in` `middles: ` `        ``if` `n !``=` `length:             ` `            ``result.append(``"0"` `+` `middle ``+` `"0"``) ` ` `  `        ``result.append(``"8"` `+` `middle ``+` `"8"``) ` `        ``result.append(``"1"` `+` `middle ``+` `"1"``) ` `        ``result.append(``"9"` `+` `middle ``+` `"6"``) ` `        ``result.append(``"6"` `+` `middle ``+` `"9"``) ` `    ``return` `result ` ` `  `# Driver Code ` `if` `__name__ ``=``=` `'__main__'``: ` `     `  `    ``# Print all Strobogrammatic  ` `    ``# number for n = 3 ` `    ``print``(strobogrammatic_num(``3``)) `

Output :

```['818', '111', '916', '619', '808', '101', '906', '609', '888', '181', '986', '689']
```

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