

- Trending Categories
Data Structure
Networking
RDBMS
Operating System
Java
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Recursive program to print all numbers less than N which consist of digits 1 or 3 only in C++
We are given an integer variable as N storing the positive integer type value. The task is to recursively print all the numbers less than given value N having digit 1, 3 or the combination of both.
Let us see various input output scenarios for this −
Input − int num = 40
Output − Recursive program to print all numbers less than N which consist of digits 1 or 3 only are: 33 31 13 11 3 1
Explanation − we are given a positive integer value as 40 stored in a variable num. Now, we will recursively find out all the numbers containing digits 1, 3 or both and those numbers less than 40 are 1, 3, 11, 13, 31, 33
Input − int num = 5
Output − Recursive program to print all numbers less than N which consist of digits 1 or 3 only are: 3 1
Explanation − we are given a positive integer value as 40 stored in a variable num. Now, we will recursively find out all the numbers containing digits 1, 3 or both and those numbers less than 5 are 1 and 3.
Input − int num = 1
Output − Wrong Input
Explanation − we are given a positive integer value as 1 stored in a variable num. Now, we will recursively find out all the numbers containing digits 1, 3 or both and those numbers less than 1 are 0 because the only positive integer less than 1 is 0 therefore, output is wrong input.
Approach used in the below program is as follows
Input an integer variable as num. Pass it to the function Recursive_Numbers(num) by passing num as the parameter to the function.
Inside the function Recursive_Numbers(num)
Declare a variable as check of type bool and set it with 1.
Check IF num greater than 0 then start WHILE temp greater than 0 AND check to 1. Set digit to temp % 10.
Check IF digit not equals 1 AND digit not equals to 3 then set check to 0. Set temp = temp / 10.
Check IF check is 1 then print num.
Make a recursive call to the function Recursive_Numbers(num - 1)
Example
#include <iostream> using namespace std; void Recursive_Numbers(int num){ bool check = 1; int temp = num; if(num > 0){ while(temp > 0 && check == 1){ int digit = temp % 10; if (digit != 1 && digit != 3){ check = 0; } temp = temp / 10; } if(check == 1){ cout<< num << " "; } Recursive_Numbers(num - 1); } } int main(){ int num = 40; if(num <= 1){ cout<<"Wrong input"; } else{ cout<<"Recursive program to print all numbers less than N which consist of digits 1 or 3 only are: "; Recursive_Numbers(num); } return 0; }
Output
If we run the above code it will generate the following Output
Recursive program to print all numbers less than N which consist of digits 1 or 3 only are: 33 31 13 11 3 1
- Related Questions & Answers
- Print all prime numbers less than or equal to N in C++
- Print all Semi-Prime Numbers less than or equal to N in C++
- Print all numbers less than N with at-most 2 unique digits in C++
- Find all factorial numbers less than or equal to n in C++
- Find maximum product of digits among numbers less than or equal to N in C++
- Find Multiples of 2 or 3 or 5 less than or equal to N in C++
- Compute sum of digits in all numbers from 1 to n
- Print numbers with digits 0 and 1 only such that their sum is N in C Program.
- Python Program to Find all Numbers in a Range which are Perfect Squares and Sum of all Digits in the Number is Less than 10
- C++ Program to Implement Sorting of Less than 100 Numbers in O(n) Complexity
- Program to Find Out Integers Less than n Containing Multiple Similar Digits in C++
- Program to find sum of two numbers which are less than the target in Python
- C++ program to find the sum of the series 1 + 1/2^2 + 1/3^3 + …..+ 1/n^n
- Print triplets with sum less than or equal to k in C Program
- Print all n-digit numbers with absolute difference between sum of even and odd digits is 1 in C++