Given an array of strings arr[]. The task is to generate the string which contains all the characters of all the strings present in array and smallest in size. There can be many such possible strings and any one is acceptable.
Examples:
Input: arr[] = {“your”, “you”, “or”, “yo”}
Output: ruyo
Explanation: The string “ruyo” is the string which contains all the characters present in all the strings in arr[].
There can be many other strings of size 4 e.g. “oury”. Those are also acceptable.Input: arr[] = {“abm”, “bmt”, “cd”, “tca”}
Output: abctdm
Approach: This problem can be solved by using the Set Data Structure. Set has the capability to remove duplicates, which is needed in this problem in order to minimize the string size. Add all the characters in the set from all the strings in the array arr[] and form a string containing all the characters remaining in the set, which is the required answer.
Below is the implementation of the above approach.
// C++ code for the above approach #include <bits/stdc++.h> using namespace std;
string minSubstr(vector<string> s) { // Stores the concatenated string
// of all the given strings
string str = "" ;
// Loop to iterate through all
// the given strings
for ( int i = 0; i < s.size(); i++)
{
str += s[i];
}
// Set to store the characters
unordered_set< char > set;
// Loop to iterate over all
// the characters in str
for ( int i = 0; i < str.length(); i++)
{
set.insert(str[i]);
}
string res = "" ;
// Loop to iterate over the set
for ( auto itr = set.begin(); itr != set.end(); itr++)
{
res = res + (*itr);
}
// Return Answer
return res;
} // Driver Code int main()
{ vector<string> arr = { "your" , "you" ,
"or" , "yo" };
cout << (minSubstr(arr));
return 0;
} // This code is contributed by Potta Lokesh |
// Java program to implement above approach import java.util.*;
public class GfG {
public static String minSubstr(String s[])
{
// Stores the concatenated string
// of all the given strings
String str = "" ;
// Loop to iterate through all
// the given strings
for ( int i = 0 ; i < s.length; i++) {
str += s[i];
}
// Set to store the characters
Set<Character> set =
new HashSet<Character>();
// Loop to iterate over all
// the characters in str
for ( int i = 0 ; i < str.length();
i++) {
set.add(str.charAt(i));
}
// Stores the required answer
String res = "" ;
Iterator<Character> itr =
set.iterator();
// Loop to iterate over the set
while (itr.hasNext()) {
res += itr.next();
}
// Return Answer
return res;
}
// Driver Code
public static void main(String[] args)
{
String arr[]
= new String[] { "your" , "you" ,
"or" , "yo" };
System.out.println(minSubstr(arr));
}
} |
# Python program to implement above approach def minSubstr(s):
# Stores the concatenated string
# of all the given strings
str = "";
# Loop to iterate through all
# the given strings
for i in range ( len (s)):
str + = s[i];
# Set to store the characters
setv = set ();
# Loop to iterate over all
# the characters in str
for i in range ( len ( str )):
setv.add( str [i]);
# Stores the required answer
res = "";
# Loop to iterate over the set
for itr in setv:
res + = itr;
# Return Answer
return res;
# Driver Code if __name__ = = '__main__' :
arr = [ "your" , "you" , "or" , "yo" ];
print (minSubstr(arr));
# This code is contributed by 29AjayKumar |
// C# program to implement above approach using System;
using System.Collections.Generic;
public class GfG {
public static String minSubstr(String []s)
{
// Stores the concatenated string
// of all the given strings
String str = "" ;
// Loop to iterate through all
// the given strings
for ( int i = 0; i < s.Length; i++) {
str += s[i];
}
// Set to store the characters
HashSet< char > set =
new HashSet< char >();
// Loop to iterate over all
// the characters in str
for ( int i = 0; i < str.Length;
i++) {
set .Add(str[i]);
}
// Stores the required answer
String res = "" ;
// Loop to iterate over the set
foreach ( char itr in set ) {
res += itr;
}
// Return Answer
return res;
}
// Driver Code
public static void Main(String[] args)
{
String []arr
= new String[] { "your" , "you" ,
"or" , "yo" };
Console.WriteLine(minSubstr(arr));
}
} // This code is contributed by 29AjayKumar |
<script> // javascript program to implement above approach public class GfG { function minSubstr(s)
{
// Stores the concatenated string
// of all the given strings
var str = "" ;
// Loop to iterate through all
// the given strings
for ( var i = 0; i < s.length; i++) {
str += s[i];
}
// Set to store the characters
var set = new Set();
// Loop to iterate over all
// the characters in str
for ( var i = 0; i < str.length;
i++) {
set.add(str.charAt(i));
}
// Stores the required answer
var res = "" ;
// Loop to iterate over the set
for (let itr of set){
res += itr;
}
// Return Answer
return res;
}
// Driver Code
var arr = [ "your" , "you" ,
"or" , "yo" ];
document.write(minSubstr(arr)); // This code is contributed by 29AjayKumar </script> |
ruyo
Time Complexity: O(N*M), where M is the average length of strings in the given array
Auxiliary Space: O(N*M)