Given some programming file names, the task is to check if they are valid or not using regular expressions. A valid programming file name follows the below conditions:
- It can contain alphabets (UpperCase or LowerCase), and digits and may contain a hyphen.
- It should contain one dot only that will be used as a suffix to save the file.
- Avoid special characters such as ?, %, #, /, and ‘:‘ in the filename.
- Every file should be saved with the right suffix used for separate programming languages.
- Some of the correct responses of the programming file extension are:
- .java
- .py
- .c
- .PHP
- .class
Valid Programming file format:
file_name.extension_of_programming_language
Examples:
Input: file_name.java
Output: TrueInput: .PHP_file_name
Output: False
Explanation: The programming file extension is not valid.
Approach: The problem can be solved based on the following idea:
Create a regex pattern to validate the number as written below:
regex= “^.*\.(java|py|c|PHP|cs|cake|cshtml|csx|cpp|cp|cc|cobol|cob|ccp|css|flux|fx| go|jsp|kt|ktm|kts|numpy|numpyw|numsc|pls|pck|pkb|pks|plbplsql|sql|perl|r|rd|rsx|sh|bash|st|cs |swift|vb|class)$“
Where,
- ^ : indicates the start of the file
- .*(dot-star): will match everything except a newline (\n).
- |(Alternation) :Acts like a boolean OR and Matches the expression before or after the |.
- \. (Escape character): matches a dot(.) character.
- *(Quantifier): matches 0 or more of the preceding token(x)Capturing group: Matches x and remembers the match. For example, /(Rahul)/ matches and remembers “Rahul” in “Rahul Chauhan”.
- $ : End of the string
Follow the below steps to implement the idea:
- Create regex expression for the programming file names.
- If the input string is empty, Therefore return false.
- Else, Use the Pattern class to compile the regex formed.
- Use the matcher function to check whether the UPI id is valid or not.
- If it is valid, return true. Otherwise, return false.
Below is the implementation of the above approach.
C++
// C++ program to validate the// Programming language file format Regular// Expression#include <bits/stdc++.h>#include <regex>using namespace std;// Function to validate the// Programming language file formatstring isValidProgrammingFileFormat(string str){ // Regex to check valid // Programming language file format. const regex pattern( "^.*\.(java|py|c|PHP|cs|cake|cshtml|csx|cpp|cp|cc|" "cobol|cob|ccp|css|flux|fx| " "go|jsp|kt|ktm|kts|numpy|numpyw|numsc|pls|pck|pkb|" "pks|plbplsql|sql|perl|r|rd|rsx|sh|bash|st|cs " "|swift|vb|class)$"); // If the string is empty return false if (str.empty()) { return "false"; } // Return true if the str // matched the ReGex if (regex_match(str, pattern)) { return "true"; } else { return "false"; }}// Driver Codeint main(){ // Test Case 1: string str1 = "file_name.java"; cout << isValidProgrammingFileFormat(str1) << endl; // Test Case 2: string str2 = "file_name01.py"; cout << isValidProgrammingFileFormat(str2) << endl; // Test Case 3: string str3 = "Java123"; cout << isValidProgrammingFileFormat(str3) << endl; // Test Case 4: string str4 = "file_name.class"; cout << isValidProgrammingFileFormat(str4) << endl; // Test Case 5: string str5 = "file_name.css"; cout << isValidProgrammingFileFormat(str5) << endl; // Test Case 6: string str6 = ".PHP_file_name"; cout << isValidProgrammingFileFormat(str6) << endl; return 0;} |
Java
// Java program to validate the// Programming language file format using// Regular Expressionimport java.io.*;import java.util.regex.*;class GFG { // Function to validate the // Programming language file format public static boolean isValidProgrammingFileFormat(String str) { // Regex to check valid Programming // language file format String regex = "^.*\\.(java|py|c|PHP|cs|cake|cshtml|csx|c|cpp|cp|cc|cobol|cob|ccp|css|flux|fx|go|jsp|kt|ktm|kts|numpy|numpyw|numsc|pls|pck|pkb|pks|plbplsql|sql|perl|r|rd|rsx|sh|bash|st|cs|swift|vb|class)$"; // Compile the ReGex Pattern p = Pattern.compile(regex); // If the string is empty return false if (str == null) { return false; } // Pattern class contains matcher() // method to find matching between // given Programming language file // format using regular expression. Matcher m = p.matcher(str); // Return if the str // matched the ReGex return m.matches(); } // Driver Code public static void main(String args[]) { // Test Case 1: String str1 = "file_name.java"; System.out.println( isValidProgrammingFileFormat(str1)); // Test Case 2: String str2 = "file_name01.py"; System.out.println( isValidProgrammingFileFormat(str2)); // Test Case 3: String str3 = "Java123"; System.out.println( isValidProgrammingFileFormat(str3)); // Test Case 4: String str4 = "file_name.class"; System.out.println( isValidProgrammingFileFormat(str4)); // Test Case 5: String str5 = "file_name.css"; System.out.println( isValidProgrammingFileFormat(str5)); // Test Case 6: String str6 = ".PHP_file_name"; System.out.println( isValidProgrammingFileFormat(str6)); }} |
Python3
# Python3 program to validate# Programming language file format using# Regular Expressionimport re# Function to validate# Programming language file formatdef isValidProgrammingFileFormat(str): # Regex to check valid Programming language # file format regex = "^.*\.(java|py|c|PHP|cs|cake|cshtml|csx|cpp|cp|cc|cobol|cob|ccp|css|flux|fx| go|jsp|kt|ktm|kts|numpy|numpyw|numsc|pls|pck|pkb|pks|plbplsql|sql|perl|r|rd|rsx|sh|bash|st|cs |swift|vb|class)$" # Compile the ReGex p = re.compile(regex) # If the string is empty # return false if (str == None): return "false" # Return if the string # matched the ReGex if(re.search(p, str)): return "true" else: return "false"# Driver codeif __name__ == '__main__': # Test Case 1: str1 = "file_name.java" print(isValidProgrammingFileFormat(str1)) # Test Case 2: str2 = "file_name01.py" print(isValidProgrammingFileFormat(str2)) # Test Case 3: str3 = "Java123" print(isValidProgrammingFileFormat(str3)) # Test Case 4: str4 = "file_name.class" print(isValidProgrammingFileFormat(str4)) # Test Case 5: str5 = "file_name.css" print(isValidProgrammingFileFormat(str5)) # Test Case 6: str6 = ".PHP_file_name" print(isValidProgrammingFileFormat(str6)) |
C#
// C# program to validate the// Programming language file format using// Regular Expressionusing System;using System.Text.RegularExpressions;public class GFG{ // Function to validate the // Programming language file format public static bool isValidProgrammingFileFormat(String str) { // Regex to check valid // Programming language file format. var regex = new Regex("^.*\\.(java|py|c|PHP|cs|cake|cshtml|csx|c|cpp|cp|cc|cobol|cob|ccp|css|flux|fx|go|jsp|kt|ktm|kts|numpy|numpyw|numsc|pls|pck|pkb|pks|plbplsql|sql|perl|r|rd|rsx|sh|bash|st|cs|swift|vb|class)$"); // If the string is empty return false if (str == null) { return false; } // Pattern class contains matcher() // method to find matching between // given Programming language file // format using regular expression. var m = regex.Match(str); // Return if the str // matched the ReGex return m.Success; } // Driver Code. public static void Main(String[] args) { // Test Case 1: var str1 = "file_name.java"; Console.WriteLine( isValidProgrammingFileFormat(str1)); // Test Case 2: var str2 = "file_name01.py"; Console.WriteLine( isValidProgrammingFileFormat(str2)); // Test Case 3: var str3 = "Java123"; Console.WriteLine( isValidProgrammingFileFormat(str3)); // Test Case 4: var str4 = "file_name.class"; Console.WriteLine( isValidProgrammingFileFormat(str4)); // Test Case 5: var str5 = "file_name.css"; Console.WriteLine( isValidProgrammingFileFormat(str5)); // Test Case 6: var str6 = ".PHP_file_name"; Console.WriteLine( isValidProgrammingFileFormat(str6)); }}// This code is contributed by Pushpesh Raj. |
Javascript
// Javascript program to validate// Programming language file format using Regular Expression// Function to validate the// Programming language file formatfunction isValidProgrammingFileFormat(str) { // Regex to check valid // Programming language file format let regex = new RegExp(/^.*\.(java|py|c|PHP|cs|cake|cshtml|csx|cpp|cp|cc|cobol|cob|ccp|css|flux|fx| go|jsp|kt|ktm|kts|numpy|numpyw|numsc|pls|pck|pkb|pks|plbplsql|sql|perl|r|rd|rsx|sh|bash|st|cs |swift|vb|class)$/); // if str // is empty return false if (str == null) { return "false"; } // Return true if the str // matched the ReGex if (regex.test(str) == true) { return "true"; } else { return "false"; }}// Driver Code// Test Case 1:let str1 = "file_name.java";console.log(isValidProgrammingFileFormat(str1));// Test Case 2:let str2 = "file_name01.py";console.log(isValidProgrammingFileFormat(str2));// Test Case 3:let str3 = "Java123";console.log(isValidProgrammingFileFormat(str3));// Test Case 4:let str4 = "file_name.class";console.log(isValidProgrammingFileFormat(str4));// Test Case 5:let str5 = "file_name.css";console.log(isValidProgrammingFileFormat(str5));// Test Case 6:let str6 = ".PHP_file_name";console.log(isValidProgrammingFileFormat(str6)); |
Output
true true false true true false
Time Complexity: O(N) for each test case, where N is the length of the given string.
Auxiliary Space: O(1)
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