Total length of string from given Array of strings composed using given characters

• Difficulty Level : Expert
• Last Updated : 31 Oct, 2021

Given a list of characters and an array of strings, find the total length of all strings in the array of strings that can be composed using the given characters.
Examples:

Input: string = [“mouse”, “me”, “bat”, “lion”], chars = “eusamotb”
Output: 10
Explanation:
The strings that can be formed using the characters “eusamotb” are “mouse” and “me” and “bat”.
Length of “mouse” is 5, length of “me” is 2, and length of “bat” is 3
Sum of all lengths = 5 + 2 + 3 = 10.
Input: string = [“hi”, “data”, “geeksforgeeks”], chars = “tiadha”
Output:
Explanation:
The strings that can be formed using the characters “tiadha” are “hi” and “data”. Where length of “hi” is 2, length of “data” is 4, the sum of all is 2 + 4 = 6.

Approach:
To solve the problem mentioned above we have to follow the steps given below:

• We can use characters from the given character string that is ‘chars’ while forming a string. We can also reuse the used characters for forming the next string
• Maintain an unordered map with character as a key and the value by keeping track of the frequency of each character from the string of chars.
• Every time we scan characters from the list of string we reduce the frequency of character from the unordered map but we have to maintain the copy of the original map so as to check the second string .
• If the key is not present in the map it creates one with default value as zero rather than throwing an error.

Below is the implementation of the above approach:

C++

 // C++ implementation to find total length// of string composed of given characters// formed from given Array of strings #include using namespace std; // Function to count the total lengthint countCharacters(    vector& strings,    string chars){    int res = 0;     // Unordered_map for    // keeping frequency of characters    unordered_map freq;     // Calculate the frequency    for (int i = 0; i < chars.length(); i++)        freq[chars[i]] += 1;     // Iterate in the N strings    for (auto st : strings) {         bool flag = true;         // Iterates in the string        for (auto c : st) {             // Checks if given character of string            // string appears in it or not            if (!freq) {                flag = false;                break;            }        }         // Adds the length of string        // if all characters are present        if (flag)            res += st.length();    }     // Return the final result    return res;} // Driver codeint main(){    vector strings        = { "hi", "data",            "geeksforgeeks" };     string chars = "tiadhae";     cout << countCharacters(strings, chars);     return 0;}

Java

 // Java implementation to find total length// of string composed of given characters// formed from given Array of stringsimport java.util.*;class GFG {     // Function to count the total lengthstatic int countCharacters(List strings,                                String chars){    int res = 0;     // Map for    // keeping frequency of characters    Map freq = new HashMap<>();     // Calculate the frequency    for (int i = 0; i < chars.length(); i++)    {        freq.put(chars.charAt(i),        freq.getOrDefault(chars.charAt(i), 0) + 1);    }     // Iterate in the N strings    for (String st : strings)    {        boolean flag = true;         // Iterates in the string        for (char c : st.toCharArray())        {             // Checks if given character of string            // string appears in it or not            if (!freq.containsKey(c))            {                flag = false;                break;            }        }         // Adds the length of string        // if all characters are present        if (flag)            res += st.length();    }     // Return the final result    return res;} // Driver codepublic static void main(String[] args){    List strings = Arrays.asList("hi", "data",                                        "geeksforgeeks");     String chars = "tiadhae";     System.out.println(countCharacters(strings, chars));}} // This code is contributed by offbeat

Python3

 # Python3 implementation to find total length# of string composed of given characters# formed from given Array of strings  # Function to count the total lengthdef countCharacters(arr, chars):    res = 0     # Unordered_map for    # keeping frequency of characters    freq = dict()     # Calculate the frequency    for i in range(len(chars)):        freq[chars[i]] = freq.get(chars[i], 0)+1     # Iterate in the N strings    for st in arr:         flag = True         # Iterates in the string        for c in st:             # Checks if given character of string            # string appears in it or not            if (c not in freq):                flag = False                break         # Adds the length of string        # if all characters are present        if (flag):            res += len(st)     # Return the final result    return res # Driver codeif __name__ == '__main__':    arr =["hi", "data", "geeksforgeeks"]     chars = "tiadhae"     print(countCharacters(arr, chars)) # This code is contributed by mohit kumar 29

C#

 // C# implementation to find total length// of string composed of given characters// formed from given Array of stringsusing System;using System.Collections.Generic;using System.Linq; class GFG{ // Function to count the total lengthstatic int countCharacters(List strings,                                string chars){    int res = 0;         // Dictionary for keeping frequency    // of characters    Dictionary freq = new Dictionary();         // Calculate the frequency    for(int i = 0; i < chars.Length; i++)    {        if(freq.ContainsKey(chars[i]))        {            freq[chars[i]]++;        }        else        {            freq.Add(chars[i],                     freq.GetValueOrDefault(                         chars[i], 0) + 1);        }    }         // Iterate in the N strings    foreach(string st in strings)    {        bool flag = true;                 // Iterates in the string        foreach (char c in st.ToCharArray())        {                         // Checks if given character of string            // string appears in it or not            if (!freq.ContainsKey(c))            {                flag = false;                break;            }        }                 // Adds the length of string        // if all characters are present        if (flag)            res += st.Length;    }         // Return the final result    return res;} // Driver codepublic static void Main(string[] args){    string []tmp = { "hi", "data",                     "geeksforgeeks" };                          List strings = tmp.ToList();     string chars = "tiadhae";     Console.Write(countCharacters(strings, chars));}} // This code is contributed by rutvik_56

Javascript


Output:
6

Time Complexity: O(n * m), where n is the length of the char and m is the length of the string.
Auxiliary Space Complexity: O(1), as the unordered map will be of size 26 only.

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