02 Combination in a String of Digits

Question

Given an input string of numbers, find all combinations of numbers that can be formed using digits in the same order. Examples:

Input : 123 
Output :1 2 3
        1 23
        12 3
        123

Input : 1234
Output :1 2 3 4 
        1 2 34 
        1 23 4 
        1 234 
        12 3 4 
        12 34 
        123 4 
        1234 

Logic

Upon observation, it can be seen that the question is either adding or not adding a space after each digit in various combinations.

1. For each iteration of the recursive function

   1. Print it either with a space or without a space

Code

/*
Visit Notebook: https://abhyas-kanaujia.gitbook.io/love-babbar-dsa-unacademy-homework/a
*/

#include <bits/stdc++.h>
using namespace std;

void printCombinations(int n, int i = 0, string combinations = "") {
    string str = to_string(n);
    if(i == str.length()) {
        cout << combinations << endl;
        return;
    }
    
    printCombinations(n, i + 1, combinations + str[i]);
    if(str[i + 1] != '\0')
        printCombinations(n, i + 1, combinations + str[i] + ' ');
    
}
c+
int main()
{
    int n;
    cin >> n;
    printCombinations(n);
    return 0;
}

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