Count the occurrence of digit K in a given number N using Recursion
Given an integer N greater than 0, the task is to find the occurrence of digit K present in the given number N.
Examples:
Input: N = 10000, K = 0
Output: 4
Explanation:
Occurrence of ‘0’ digit in 10000 is 4.Input: N = 51435, K = 5
Output: 2
Explanation:
Occurrence of ‘5’ digit in 51435 is 2
Approach: The idea is to use recursion to extract the least significant digit of the number in each step and Check that the digit extracted is equal to the given digit K or not. Finally, recurse for checking the next digits of the number by computing the integer division of that number by 10.
Below is the implementation of the above approach:
C++
// C++ implementation to count // the occurrence of a digit in // number using Recursion #include <bits/stdc++.h> using namespace std; // Function to count the digit K // in the given number N int countdigits(int n, int k) { if (n == 0) return 0; // Extracting least // significant digit int digit = n % 10; if (digit == k) return 1 + countdigits(n / 10, k); return countdigits(n / 10, k); } // Driver Code int main() { int n = 1000; int k = 0; cout << countdigits(n, k) << endl; return 0; } |
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Java
// Java implementation to count // the occurrence of a digit in // number using Recursion import java.util.*; class GFG { // Function to count the digit K // in the given number N static double countdigits(int n, int k) { if (n == 0) return 0; // Extracting least // significant digit int digit = n % 10; if (digit == k) return 1 + countdigits(n / 10, k); return countdigits(n / 10, k); } // Driver Code public static void main(String[] args) { int n = 1000; int k = 0; System.out.println(countdigits(n, k)); } } |
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Python3
# Python implementation to count # the occurrence of a digit in # number using Recursion # Function to count the digit K # in the given number N def countdigits(n, k): if n == 0: return 0 # Extracting least # significant digit digit = n % 10 if digit == k: return 1 + countdigits(n / 10, k) return countdigits(n / 10, k) # Driver Code if __name__ == "__main__": n = 1000; k = 0; print(countdigits(n, k)) |
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C#
// C# implementation to count // the occurrence of a digit in // number using Recursion using System; class GFG { // Function to count the digit K // in the given number N static double countdigits(int n, int k) { if (n == 0) return 0; // Extracting least // significant digit int digit = n % 10; if (digit == k) return 1 + countdigits(n / 10, k); return countdigits(n / 10, k); } // Driver Code static public void Main() { int n = 1000; int k = 0; Console.WriteLine(countdigits(n, k)); } } |
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Output:
3
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Improved By : Akanksha_Rai
