Generate two output strings depending upon occurrence of character in input string.

Given an input string str[], generate two output strings. One of which consists of those character which occurs only once in input string and second which consists of multi-time occurring characters. Output strings must be sorted.
Examples:

Input : str[] = "geeksforgeeks"
Output : String with characters occurring once:
for
String with characters occurring multiple times:
egks

Input : str[] = "geekspractice"
Output : String with characters occurring once:
agikprst
String with characters occurring multiple times:
ce

Approach : We follow total two steps to generate the both output strings. 
Step 1: Create a count array and count occurrences of characters in the given input string. 
Step 2: Check count array for each position ‘i’ which leads to three possible conditions : 
a) If count value is 1, append character in first output string. 
b) If count value is greater than 1, append character in second output string. 
c) If count value is 0 do nothing.
Time Complexity for above approach is O(n). 
Auxiliary Space required is O(1). 

C++

// CPP program to print two strings
// made of character occurring once
// and multiple times
#include <bits/stdc++.h>
using namespace std;

const int MAX_CHAR = 256;

// function to print two strings
// generated from single string one
// with characters occurring once
// other with character occurring
// multiple of times
void printDuo(string &str)
{
    // initialize hashtable with zero
    // entry
    int countChar[MAX_CHAR] = { 0 };

    // perform hashing for input string
    int n = str.length();
    for (int i = 0; i < n; i++)
        countChar[str[i] - 'a']++;

    // generate string (str1) consisting
    // char occurring once and string
    // (str2) consisting char occurring
    // multiple times
    string str1 = "", str2 = "";
    for (int i = 0; i < MAX_CHAR; i++) {
        if (countChar[i] > 1)
            str2 = str2 + (char)(i + 'a');
        else if (countChar[i] == 1)
            str1 = str1 + (char)(i + 'a');
    }

    // print both strings
    cout << "String with characters occurring "
         <<  "once:\n";
    cout << str1 << "\n";
    cout << "String with characters occurring "
         << "multiple times:\n";
    cout << str2 << "\n";
}

// driver program
int main()
{
    string str = "lovetocode";
    printDuo(str);
    return 0;
}

Java

// Java program to print two strings
// made of character occurring once
// and multiple times

class GFG {

    final static int MAX_CHAR = 256;

// function to print two strings
// generated from single string one
// with characters occurring once
// other with character occurring
// multiple of times
    static void printDuo(String str) {
        // initialize hashtable with zero
        // entry
        int countChar[] = new int[MAX_CHAR];

        // perform hashing for input string
        int n = str.length();
        for (int i = 0; i < n; i++) {
            countChar[str.charAt(i) - 'a']++;
        }

        // generate string (str1) consisting
        // char occurring once and string
        // (str2) consisting char occurring
        // multiple times
        String str1 = "", str2 = "";
        for (int i = 0; i < MAX_CHAR; i++) {
            if (countChar[i] > 1) {
                str2 = str2 + (char) (i + 'a');
            } else if (countChar[i] == 1) {
                str1 = str1 + (char) (i + 'a');
            }
        }

        // print both strings
        System.out.print("String with characters occurring "
                + "once:\n");
        System.out.print(str1 + "\n");
        System.out.print("String with characters occurring "
                + "multiple times:\n");
        System.out.print(str2 + "\n");
        System.out.print("");
    }

// driver program
    public static void main(String[] args) {
        String str = "lovetocode";
        printDuo(str);

    }
}
//this code contributed by 29AJayKumar

Python3

# Python3 program to print two strings
# made of character occurring once
# and multiple times

MAX_CHAR = 256

# function to print two strings
# generated from single string one
# with characters occurring once
# other with character occurring
# multiple of times
def printDuo(string):

    # initialize hashtable with zero
    # entry
    countChar = [0 for i in range(MAX_CHAR)]

    # perform hashing for input string
    n = len(string)
    for i in range(n):
        countChar[ord(string[i]) - ord('a')] += 1

    # generate string (str1) consisting
    # char occurring once and string
    # (str2) consisting char occurring
    # multiple times
    str1 = ""
    str2 = ""
    for i in range(MAX_CHAR):
        if (countChar[i] > 1):
            str2 = str2 + chr(i + ord('a'))
        elif (countChar[i] == 1):
            str1 = str1 + chr(i + ord('a'))

    # print both strings
    print("String with characters occurring once:",
                                        "\n", str1)
    print("String with characters occurring",
               "multiple times:", "\n", str2)

# Driver Code
string = "lovetocode"
printDuo(string)

# This code is contributed by
# Mohit kumar 29

C#

// C# program to print two strings
// made of character occurring once
// and multiple times
using System;

class GFG
{
static int MAX_CHAR = 256;

// function to print two strings
// generated from single string one
// with characters occurring once
// other with character occurring
// multiple of times
static void printDuo(string str)
{
    // initialize hashtable with zero
    // entry
    int[] countChar = new int[MAX_CHAR];

    // perform hashing for input string
    int n = str.Length;
    for (int i = 0; i < n; i++)
    {
        countChar[str[i] - 'a']++;
    }

    // generate string (str1) consisting
    // char occurring once and string
    // (str2) consisting char occurring
    // multiple times
    string str1 = "", str2 = "";
    for (int i = 0; i < MAX_CHAR; i++)
    {
        if (countChar[i] > 1)
        {
            str2 = str2 + (char) (i + 'a');
        }
        else if (countChar[i] == 1)
        {
            str1 = str1 + (char) (i + 'a');
        }
    }

    // print both strings
    Console.Write("String with characters "+
                       "occurring once:\n");
    Console.Write(str1 + "\n");
    Console.Write("String with characters occurring " +
                                  "multiple times:\n");
    Console.Write(str2 + "\n");
    Console.Write("");
}

// Driver Code
public static void Main()
{
    string str = "lovetocode";
    printDuo(str);
}
}

// This code is contributed by ita_c

Javascript

<script>

// javascript program to print two strings
// made of character occurring once
// and multiple times

var MAX_CHAR = 256;

// function to print two strings
// generated from single string one
// with characters occurring once
// other with character occurring
// multiple of times
function printDuo(str)
{
    // initialize hashtable with zero
    // entry
    var countChar = Array(MAX_CHAR).fill(0);

    // perform hashing for input string
    var n = str.length;
    for (var i = 0; i < n; i++)
        countChar[str[i].charCodeAt(0) - 'a'.charCodeAt(0)]++;

    // generate string (str1) consisting
    // char occurring once and string
    // (str2) consisting char occurring
    // multiple times
    var str1 = "", str2 = "";
    for (var i = 0; i < MAX_CHAR; i++) {
        if (countChar[i] > 1)
            str2 = str2 + String.fromCharCode(i + 'a'.charCodeAt(0));
        else if (countChar[i] == 1)
            str1 = str1 + String.fromCharCode(i + 'a'.charCodeAt(0));
    }

    // print both strings
    document.write( "String with characters occurring "
         +  "once:<br>");
    document.write( str1 + "<br>");
    document.write( "String with characters occurring "
         + "multiple times:<br>");
    document.write( str2 + "<br>");
}

// driver program
var str = "lovetocode";
printDuo(str);

</script>

Output:

String with characters occurring once:
cdltv
String with characters occurring multiple times:
eo

Time complexity : O(n) 
Auxiliary Space : O(1)

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