# Check if a number is formed by Concatenation of 1, 14 or 144 only

• Difficulty Level : Expert
• Last Updated : 08 Nov, 2021

Given a number . The task is to check if the number is formed by concatenating the numbers 1, 14 and 144 only any number of times and in any order.
If it is possible, print YES otherwise print NO.
Example:

```Input: N = 141411
Output: YES

Input: N = 14134
Output: NO```

The idea is to fetch single digit, double digit and triple digit numbers from the end and check if any of them matches with 1, 14 and 144 respectively. If any of them matches, divide the number with that and repeat the above step until the number is greater than zero.
Below is the implementation of using above approach:

## C++

 `// C++ program to check if a number is formed``// by Concatenation of 1, 14 or 144 only` `#include ``using` `namespace` `std;` `// Function to check if a number is formed``// by Concatenation of 1, 14 or 144 only``string checkNumber(``int` `N)``{``    ``int` `temp = N;` `    ``while` `(temp > 0) {``        ``// check for each possible digit``        ``// if given number consist other then``        ``// 1, 14, 144 print NO else print YES``        ``if` `(temp % 1000 == 144)``            ``temp /= 1000;``        ``else` `if` `(temp % 100 == 14)``            ``temp /= 100;``        ``else` `if` `(temp % 10 == 1)``            ``temp /= 10;``        ``else` `{``            ``return` `"NO"``;``        ``}``    ``}` `    ``return` `"YES"``;``}` `// Driver Code``int` `main()``{``    ``int` `N = 1414;` `    ``cout << checkNumber(N);` `    ``return` `0;``}`

## Java

 `// Java program to check if a number is formed``// by Concatenation of 1, 14 or 144 only` `import` `java.io.*;` `class` `GFG {``    `  `// Function to check if a number is formed``// by Concatenation of 1, 14 or 144 only``static` `String checkNumber(``int` `N)``{``    ``int` `temp = N;` `    ``while` `(temp > ``0``) {``        ``// check for each possible digit``        ``// if given number consist other then``        ``// 1, 14, 144 print NO else print YES``        ``if` `(temp % ``1000` `== ``144``)``            ``temp /= ``1000``;``        ``else` `if` `(temp % ``100` `== ``14``)``            ``temp /= ``100``;``        ``else` `if` `(temp % ``10` `== ``1``)``            ``temp /= ``10``;``        ``else` `{``            ``return` `"NO"``;``        ``}``    ``}` `    ``return` `"YES"``;``}` `// Driver Code`  `    ``public` `static` `void` `main (String[] args) {``        ``int` `N = ``1414``;` `    ``System.out.println(checkNumber(N));``    ``}``}``// This code is contributed by anuj_67..`

## Python 3

 `# Python 3 program to check if a``# number is formed by Concatenation``# of 1, 14 or 144 only` `# Function to check if a number is formed``# by Concatenation of 1, 14 or 144 only``def` `checkNumber(N):``    ``temp ``=` `N` `    ``while` `(temp > ``0``):``        ` `        ``# check for each possible digit``        ``# if given number consist other then``        ``# 1, 14, 144 print NO else print YES``        ``if` `(temp ``%` `1000` `=``=` `144``):``            ``temp ``/``=` `1000``        ``elif` `(temp ``%` `100` `=``=` `14``):``            ``temp ``/``=` `100``        ``elif` `(temp ``%` `10` `=``=` `1``):``            ``temp ``/``=` `10``        ``else``:``            ``return` `"YES"` `    ``return` `"NO"` `# Driver Code``N ``=` `1414``;` `print``(checkNumber(N));` `# This code is contributed``# by Akanksha Rai`

## C#

 `// C# program to check if a number is formed``// by Concatenation of 1, 14 or 144 only` `using` `System;` `class` `GFG {``    `  `// Function to check if a number is formed``// by Concatenation of 1, 14 or 144 only``static` `String checkNumber(``int` `N)``{``    ``int` `temp = N;` `    ``while` `(temp > 0) {``        ``// check for each possible digit``        ``// if given number consist other then``        ``// 1, 14, 144 print NO else print YES``        ``if` `(temp % 1000 == 144)``            ``temp /= 1000;``        ``else` `if` `(temp % 100 == 14)``            ``temp /= 100;``        ``else` `if` `(temp % 10 == 1)``            ``temp /= 10;``        ``else` `{``            ``return` `"NO"``;``        ``}``    ``}` `    ``return` `"YES"``;``}` `// Driver Code`  `    ``public` `static` `void` `Main () {``        ``int` `N = 1414;` `    ``Console.WriteLine(checkNumber(N));``    ``}``}``// This code is contributed by anuj_67..`

## PHP

 ` 0)``    ``{``        ``// check for each possible digit``        ``// if given number consist other then``        ``// 1, 14, 144 print NO else print YES``        ``if` `(``\$temp` `% 1000 == 144)``            ``\$temp` `/= 1000;``        ``else` `if` `(``\$temp` `% 100 == 14)``            ``\$temp` `/= 100;``        ``else` `if` `(``\$temp` `% 10 == 1)``            ``\$temp` `/= 10;``        ``else``        ``{``            ``return` `"YES"``;``        ``}``    ``}` `    ``return` `"NO"``;``}` `// Driver Code``\$N` `= 1414;``echo` `checkNumber(``\$N``);` `// This code is contributed by Tushil``?>`

## Javascript

 ``
Output:
`YES`

Time Complexity: O(N/10)

Auxiliary Space: O(1)

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