# Check if a given number is Fancy

A fancy number is one which when rotated 180 degrees is the same. Given a number, find whether it is fancy or not.

180 degree rotations of 6, 9, 1, 0 and 8 are 9, 6, 1, 0 and 8 respectively

Examples:

```Input:  num =  96
Output: Yes
If we rotate given number by 180, we get same number

Input:  num =  916
Output: Yes
If we rotate given number by 180, we get same number

Input:  num =  996
Output: No

Input:  num =  121
Output: No
```

We strongly recommend you to minimize your browser and try this yourself first.

The idea is to create a map to store fancy pair mappings. After creating map, traverse given number from both ends and if at any point characters at current ends are not fancy pairs, return false. This algorithm is similar to palindrome check algorithm.

Below is the implementation of above idea.

## C++

 `// C++ program to find if a given number is fancy or not. ` `#include ` `using` `namespace` `std; ` ` `  `bool` `isFancy(string& num) ` `{ ` `    ``// To store mappings of fancy pair characters. For example ` `    ``// 6 is paired with 9 and 9 is paired with 6. ` `    ``map<``char``, ``char``> fp; ` `    ``fp[``'0'``] = ``'0'``; ` `    ``fp[``'1'``] = ``'1'``; ` `    ``fp[``'6'``] = ``'9'``; ` `    ``fp[``'8'``] = ``'8'``; ` `    ``fp[``'9'``] = ``'6'``; ` ` `  `    ``// Find number of digits in given number ` `    ``int` `n = num.length(); ` ` `  `    ``// Traverse from both ends, and compare characters one by one ` `    ``int` `l = 0, r = n-1; ` `    ``while` `(l<=r) ` `    ``{ ` `        ``// If current characters at both ends are not fancy pairs ` `        ``if` `(fp.find(num[l]) == fp.end() || fp[num[l]] != num[r]) ` `            ``return` `false``; ` `        ``l++; ` `        ``r--; ` `    ``} ` `    ``return` `true``; ` `} ` ` `  `// Driver program ` `int` `main() ` `{ ` `    ``string str = ``"9088806"``; ` `    ``isFancy(str)? cout << ``"Yes"``: cout << ``"No"``; ` `    ``return` `0; ` `} `

## Java

 `// Java program to find if a given number  ` `// is fancy or not ` `import` `java.util.*; ` ` `  `class` `GFG  ` `{ ` `static` `boolean` `isFancy(String num)  ` `{  ` `    ``// To store mappings of fancy pair characters.  ` `    ``// For example 6 is paired with 9 and 9 is paired with 6.  ` `    ``Map fp = ``new` `HashMap();  ` `                                     `  `    ``fp. put(``'0'``, ``'0'``);  ` `    ``fp. put(``'1'``, ``'1'``);  ` `    ``fp. put(``'6'``, ``'9'``);  ` `    ``fp. put(``'8'``, ``'8'``);  ` `    ``fp. put(``'9'``, ``'6'``);  ` ` `  `    ``// Find number of digits in given number  ` `    ``int` `n = num.length();  ` ` `  `    ``// Traverse from both ends,  ` `    ``// and compare characters one by one  ` `    ``int` `l = ``0``, r = n-``1``;  ` `    ``while` `(l <= r)  ` `    ``{  ` `        ``// If current characters at both ends  ` `        ``// are not fancy pairs  ` `        ``if` `(!fp.containsKey(num.charAt(l)) ||  ` `             ``fp.get(num.charAt(l)) != num.charAt(r))  ` `            ``return` `false``;  ` `        ``l++;  ` `        ``r--;  ` `    ``}  ` `    ``return` `true``;  ` `}  ` ` `  `// Driver Code ` `public` `static` `void` `main(String[] args)  ` `{ ` `    ``String str = ``"9088806"``;  ` `    ``if``(isFancy(str)) ` `        ``System.out.println(``"Yes"``); ` `    ``else` `        ``System.out.println(``"No"``); ` `} ` `}  ` ` `  `// This code is contributed by PrinciRaj1992 `

## C#

 `// C# program to find if a given number  ` `// is fancy or not ` `using` `System; ` `using` `System.Collections.Generic; ` ` `  `class` `GFG  ` `{ ` `static` `bool` `isFancy(String num)  ` `{  ` `    ``// To store mappings of fancy pair characters.  ` `    ``// For example 6 is paired with 9 and 9 is paired with 6.  ` `    ``Dictionary<``char``, ``char``> fp = ``new` `Dictionary<``char``, ``char``>(); ` `                                     `  `    ``fp.Add(``'0'``, ``'0'``);  ` `    ``fp.Add(``'1'``, ``'1'``);  ` `    ``fp.Add(``'6'``, ``'9'``);  ` `    ``fp.Add(``'8'``, ``'8'``);  ` `    ``fp.Add(``'9'``, ``'6'``);  ` ` `  `    ``// Find number of digits in given number  ` `    ``int` `n = num.Length;  ` ` `  `    ``// Traverse from both ends,  ` `    ``// and compare characters one by one  ` `    ``int` `l = 0, r = n - 1;  ` `    ``while` `(l <= r)  ` `    ``{  ` `        ``// If current characters at both ends  ` `        ``// are not fancy pairs  ` `        ``if` `(!fp.ContainsKey(num[l]) ||  ` `             ``fp[num[l]] != num[r])  ` `            ``return` `false``;  ` `        ``l++;  ` `        ``r--;  ` `    ``}  ` `    ``return` `true``;  ` `}  ` ` `  `// Driver Code ` `public` `static` `void` `Main(String[] args)  ` `{ ` `    ``String str = ``"9088806"``;  ` `    ``if``(isFancy(str)) ` `        ``Console.WriteLine(``"Yes"``); ` `    ``else` `        ``Console.WriteLine(``"No"``); ` `} ` `}  ` ` `  `// This code is contributed by Rajput-Ji `

Output:

`Yes`

Thanks to Gaurav Ahirwar for suggesting above solution.

My Personal Notes arrow_drop_up

Improved By : princiraj1992, Rajput-Ji

Article Tags :
Practice Tags :

2

Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.