# Most similar string

Given a string str and an array of strings arr[] of size N, the task is to print a string from arr[], which has maximum count of matching characters with str.

Examples:

Input: str = “vikas”, N = 3, arr[] = [“preeti”, “khusbu”, “katherina”]
Output: “katherina”
Explanation:
Number of similar characters between Str and each string in D[ ] are,
“preeti” = 1
“khusbu” = 2
“katherina” = 3
Hence, “katherina” has maximum matching characters.

Input: str = “gfg”, N = 3, arr[] = [“goal”, “fog”, “abc”]
Output: “fog”
Explanation:
Number of similar characters between Str and each string in D[ ] are,
“goal” = 1
“fog” = 2
“abc” = 0
Hence, “fog” has maximum matching characters.

Approach: The idea is to consider each string of array arr[], and compare each of its character with the given string str. Keep track of the maximum number of matching characters and corresponding string. Also, make sure to remove the duplicates from each string. Below are the steps:

1. Create a variable maxVal and a variable val, to keep track of maximum number of matching characters and corresponding string respectively.
2. Traverse the array arr[] and remove duplicates from each string. Also, remove duplicates from Str.
3. For each string of arr[], compare it with the given string str, and count the number of matching characters.
4. Keep updating maxVal with the maximum number of matching characters and val with corresponding string.
5. Finally, print the value of val after the above operations.

Below is the implementation of the above approach:

## Java

 `// Java program for the above appraoch ` `import` `java.util.*; ` `import` `java.io.*; ` ` `  `public` `class` `GFG { ` ` `  `    ``// Function that print string which ` `    ``// has maximum similar characters ` `    ``private` `static` `void` `    ``maxMatchingChar(ArrayList list, ` `                    ``int` `n, ``char` `ch[]) ` `    ``{ ` ` `  `        ``String val = ``""``; ` ` `  `        ``int` `maxVal = Integer.MIN_VALUE; ` ` `  `        ``for` `(String s : list) { ` ` `  `            ``// Count matching characters ` `            ``int` `matchingchar = matchingChar( ` `                ``s.toLowerCase(), ch); ` ` `  `            ``// Update maxVal if needed ` `            ``if` `(matchingchar > maxVal) { ` `                ``maxVal = matchingchar; ` `                ``val = s; ` `            ``} ` `        ``} ` ` `  `        ``System.out.print(val + ``" "``); ` `    ``} ` ` `  `    ``// Function that returns the count ` `    ``// of number of matching characters ` `    ``private` `static` `int` `matchingChar( ` `        ``String s, ``char``[] ch) ` `    ``{ ` ` `  `        ``int` `freq = ``0``, c = ch.length; ` ` `  `        ``// Traverse the character array ` `        ``for` `(``int` `i = ``0``; i < c; i++) { ` ` `  `            ``// If character matches ` `            ``// then increment the count ` `            ``if` `(s.contains( ` `                    ``String.valueOf(ch[i]))) { ` `                ``freq++; ` `            ``} ` `        ``} ` ` `  `        ``return` `freq; ` `    ``} ` ` `  `    ``// Function to remove duplicate ` `    ``// characters ` `    ``private` `static` `char``[] removeDuplicate(String str) ` `    ``{ ` `        ``// To keep unique character only ` `        ``HashSet set ` `            ``= ``new` `HashSet(); ` ` `  `        ``int` `c = str.length(); ` ` `  `        ``// Inserting character in hashset ` `        ``for` `(``int` `i = ``0``; i < c; i++) { ` ` `  `            ``set.add(str.charAt(i)); ` `        ``} ` ` `  `        ``char` `arr[] = ``new` `char``[set.size()]; ` `        ``int` `index = ``0``; ` ` `  `        ``// Update string with unique characters ` `        ``for` `(``char` `s : set) { ` ` `  `            ``arr[index] = s; ` `            ``index++; ` `        ``} ` ` `  `        ``// Return the char array ` `        ``return` `arr; ` `    ``} ` ` `  `    ``// Driver Code ` `    ``public` `static` `void` `main( ` `        ``String[] args) ``throws` `Exception ` `    ``{ ` `        ``int` `n = ``3``; ` `        ``String str = ``"Vikas"``; ` `        ``String D[] = { ``"preeti"``, ``"khusbu"``, ``"katherina"` `}; ` ` `  `        ``// Removing duplicate and ` `        ``// convert to lowercase ` `        ``char` `ch[] ` `            ``= removeDuplicate(str.toLowerCase()); ` ` `  `        ``ArrayList list ` `            ``= ``new` `ArrayList(); ` ` `  `        ``// Insert each string in the list ` `        ``for` `(``int` `i = ``0``; i < n; i++) { ` ` `  `            ``list.add(D[i]); ` `        ``} ` ` `  `        ``// Function Call ` `        ``maxMatchingChar(list, n, ch); ` `    ``} ` `}`

## C#

 `// C# program for the above appraoch ` `using` `System; ` `using` `System.Collections.Generic; ` ` `  `class` `GFG{ ` ` `  `// Function that print string which ` `// has maximum similar characters ` `private` `static` `void` `maxMatchingChar(List list, ` `                                    ``int` `n, ``char` `[]ch) ` `{ ` `    ``String val = ``""``; ` ` `  `    ``int` `maxVal = ``int``.MinValue; ` ` `  `    ``foreach``(String s ``in` `list)  ` `    ``{ ` ` `  `        ``// Count matching characters ` `        ``int` `matchingchar = matchingChar( ` `                           ``s.ToLower(), ch); ` ` `  `        ``// Update maxVal if needed ` `        ``if` `(matchingchar > maxVal) ` `        ``{ ` `            ``maxVal = matchingchar; ` `            ``val = s; ` `        ``} ` `    ``} ` `    ``Console.Write(val + ``" "``); ` `} ` ` `  `// Function that returns the count ` `// of number of matching characters ` `private` `static` `int` `matchingChar(String s, ``char``[] ch) ` `{ ` `    ``int` `freq = 0, c = ch.Length; ` ` `  `    ``// Traverse the character array ` `    ``for``(``int` `i = 0; i < c; i++) ` `    ``{ ` ` `  `        ``// If character matches ` `        ``// then increment the count ` `        ``if` `(s.Contains(String.Join(``""``, ch[i]))) ` `        ``{ ` `            ``freq++; ` `        ``} ` `    ``} ` `    ``return` `freq; ` `} ` ` `  `// Function to remove duplicate ` `// characters ` `private` `static` `char``[] removeDuplicate(String str) ` `{ ` `     `  `    ``// To keep unique character only ` `    ``HashSet<``char``> ``set` `= ``new` `HashSet<``char``>(); ` ` `  `    ``int` `c = str.Length; ` ` `  `    ``// Inserting character in hashset ` `    ``for``(``int` `i = 0; i < c; i++) ` `    ``{ ` `        ``set``.Add(str[i]); ` `    ``} ` ` `  `    ``char` `[]arr = ``new` `char``[``set``.Count]; ` `    ``int` `index = 0; ` ` `  `    ``// Update string with unique characters ` `    ``foreach``(``char` `s ``in` `set``)  ` `    ``{ ` `        ``arr[index] = s; ` `        ``index++; ` `    ``} ` ` `  `    ``// Return the char array ` `    ``return` `arr; ` `} ` ` `  `// Driver Code ` `public` `static` `void` `Main(String[] args)  ` `{ ` `    ``int` `n = 3; ` `    ``String str = ``"Vikas"``; ` `    ``String []D = { ``"preeti"``, ``"khusbu"``,  ` `                   ``"katherina"` `}; ` ` `  `    ``// Removing duplicate and ` `    ``// convert to lowercase ` `    ``char` `[]ch = removeDuplicate(str.ToLower()); ` ` `  `    ``List list = ``new` `List(); ` ` `  `    ``// Insert each string in the list ` `    ``for``(``int` `i = 0; i < n; i++) ` `    ``{ ` `        ``list.Add(D[i]); ` `    ``} ` ` `  `    ``// Function call ` `    ``maxMatchingChar(list, n, ch); ` `} ` `} ` ` `  `// This code is contributed by Rohit_ranjan  `

Output:

```katherina
```

Time Complexity: O(N*M) where M is the maximum length of a string.
Auxiliary space: O(M)

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