# Check Whether a number is Duck Number or not

A Duck number is a positive number which has zeroes present in it, For example 3210, 8050896, 70709 are all Duck numbers. Please note that a numbers with only leading 0s is not considered as Duck Number. For example, numbers like 035 or 0012 are not considered as Duck Numbers. A number like 01203 is considered as Duck because there is a non-leading 0 present in it.

Examples :

Input : 707069
Output : It is a duck number.
Explanation: 707069 does not contains zeros at the beginning.

Input : 02364
Output : It is not a duck number.
Explanation: in 02364 there is a zero at the beginning of the number.

## C++

 `// C++ Program to check whether ` `// a number is Duck Number or not. ` `#include ` `using` `namespace` `std; ` ` `  `// Function to check whether ` `// given number is duck number or not. ` `bool` `check_duck(string num) ` `{ ` `    ``// Ignore leading 0s ` `    ``int` `i = 0, n = num.length(); ` `    ``while` `(i < n && num[i] == ``'0'``) ` `        ``i++; ` ` `  `    ``// Check remaining digits ` `    ``while` `(i < n) { ` `        ``if` `(num[i] == ``'0'``) ` `            ``return` `true``; ` `        ``i++; ` `    ``} ` ` `  `    ``return` `false``; ` `} ` ` `  `// Driver Method ` `int` `main(``void``) ` `{ ` `    ``string num = ``"1023"``; ` `    ``if` `(check_duck(num)) ` `        ``cout << ``"It is a duck number\n"``; ` `    ``else` `        ``cout << ``"It is not a duck number\n"``; ` ` `  `    ``return` `0; ` `}`

## Java

 `// Java Program to check whether a ` `// number is Duck Number or not. ` ` `  `import` `java.io.*; ` `class` `GFG { ` ` `  `    ``// Function to check whether ` `    ``// the given number is duck number or not. ` `    ``static` `boolean` `check_duck(String num) ` `    ``{ ` `        ``// Ignore leading 0s ` `        ``int` `i = ``0``, n = num.length(); ` `        ``while` `(i < n && num.charAt(i) == ``'0'``) ` `            ``i++; ` ` `  `        ``// Check remaining digits ` `        ``while` `(i < n) { ` `            ``if` `(num.charAt(i) == ``'0'``) ` `                ``return` `true``; ` `            ``i++; ` `        ``} ` ` `  `        ``return` `false``; ` `    ``} ` ` `  `    ``// Driver Method ` `    ``public` `static` `void` `main(String args[]) ``throws` `IOException ` `    ``{ ` `        ``String num = ``"1023"``; ` `        ``if` `(check_duck(num)) ` `            ``System.out.println(``"It is a duck number"``); ` `        ``else` `            ``System.out.println(``"It is not a duck number"``); ` `    ``} ` `} `

## Python

 `# Python program to check whether a number is Duck Number or not. ` ` `  `# Function to check whether  ` `# the given number is duck number or not. ` `def` `check_duck(num) : ` ` `  `    ``# Length of the number(number of digits) ` `    ``n ``=` `len``(num)  ` `    `  `    ``# Ignore leading 0s ` `    ``i ``=` `0` `    ``while` `(i < n ``and` `num[i] ``=``=` `'0'``) : ` `        ``i ``=` `i ``+` `1` ` `  `    ``# Check remaining digits ` `    ``while` `(i < n) :  ` `        ``if` `(num[i] ``=``=` `"0"``) : ` `            ``return` `True`  `        ``i ``=` `i ``+` `1` ` `  `    ``return` `False`  `     `  ` `  `# Driver Method ` `num1 ``=` `"1023"`  `if``(check_duck(num1)) : ` `    ``print` `"It is a duck number"` `else` `: ` `    ``print` `"It is not a duck number"` ` `  `# Write Python3 code here `

## C#

 `// C# Program to check whether a  ` `// number is Duck Number or not. ` `using` `System; ` ` `  `class` `GFG { ` `     `  `    ``// Function to check whether  ` `    ``// the given number is duck ` `    ``// number or not. ` `    ``static` `bool` `check_duck( String num) ` `    ``{ ` `         `  `        ``// Ignore leading 0s ` `        ``int` `i = 0, n = num.Length; ` `        ``while` `(i < n && num[i] == ``'0'``) ` `            ``i++; ` ` `  `        ``// Check remaining digits ` `        ``while` `(i < n) { ` `            ``if` `(num[i] == ``'0'``) ` `                ``return` `true``; ` `            ``i++; ` `        ``} ` ` `  `        ``return` `false``; ` `    ``} ` `     `  ` `  `    ``// Driver Method ` `    ``public` `static` `void` `Main() ` `    ``{ ` `         `  `        ``String num1 = ``"1023"``;  ` `         `  `        ``// checking number1 ` `        ``if``( check_duck(num1)) ` `            ``Console.Write(``"It is a "` `                      ``+ ``"duck number"``); ` `        ``else` `            ``Console.Write(``"It is not "` `                    ``+ ``"a duck number"``); ` `    ``} ` `} ` ` `  `// This code is contributed by ` `// nitin mittal. `

Output :

```It is a duck number.
```

This article is contributed by Nikita Tiwari. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.