Appplications based Regex Solved

imKashyap · imKashyap · commit 9d08c530aa28 · 2021-04-21T09:34:15.000+05:30
diff --git a/Hackerrank/Regex/Applications/DetectDomainName.java b/Hackerrank/Regex/Applications/DetectDomainName.java
@@ -0,0 +1,50 @@
+import java.util.*;
+import java.util.regex.*;
+
+public class Solution {
+    private final static Matcher matcher = Pattern.compile(
+        //Http
+        "(?:https?://)"
+        
+        //Domain
+        +"(?<domain>[-a-z0-9_~]{1,63}(?:\\.[-a-z0-9_~]{1,63}){1,126})"
+        
+        //Port
+        +"(?::[0-9]{1,5})?"
+        
+        //Path
+        +"(?:/[^\\s?]*)?"
+        
+        //Parameters
+        +"(?:\\?[-a-z0-9_~]+=[-a-z0-9_~]*(?:&[-a-z0-9_~]+=[-a-z0-9_~]*)*)?",
+        
+        Pattern.CASE_INSENSITIVE
+    ).matcher("");
+    
+    public static void main(String[] args) {
+        Scanner in = new Scanner(System.in);
+        Set<String> domains = new TreeSet<String>();
+        
+        //Find domains
+        int N = Integer.parseInt(in.nextLine());
+        while (N-- > 0) {
+            String htmlFrag = in.nextLine();
+            matcher.reset(htmlFrag);
+            while (matcher.find()) {
+                String domain = matcher.group("domain").toLowerCase();
+                if (domain.length() < 254) {
+                    if (domain.startsWith("www.") || domain.startsWith("ww2.")) {
+                        domain = domain.substring(4);
+                    }
+                    domains.add(domain);
+                }
+            }
+        }
+        
+        //Print domains
+        N = domains.size();
+        for (String domain : domains) {
+            System.out.print(domain + (--N > 0 ? ";" : ""));
+        }
+    }
+}
diff --git a/Hackerrank/Regex/Applications/DetectEmail.java b/Hackerrank/Regex/Applications/DetectEmail.java
@@ -0,0 +1,62 @@
+import java.io.*;
+import java.util.*;
+import java.util.regex.*;
+
+public class Solution {
+
+    public static void main(String[] args) throws IOException{
+        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
+        Scanner in = new Scanner(System.in);
+        Matcher matcher = Pattern.compile(
+            "(?<local>"
+            
+                + "[-a-zA-Z0-9!#$%&'*+/=?^_`{|}~.]+(?:\\.\\\"(?:[- a-zA-Z0-9!#$%&'*+/=?^_`{|}~.(),:;<>@\\[\\]]|\\\\\"|\\\\)+\\\"\\.[- a-zA-Z0-9!#$%&'*+/=?^_`{|}~.]+)?"
+                
+                + "|"
+                
+                + "\\\"(?:[- a-zA-Z0-9!#$%&'*+/=?^_`{|}~.(),:;<>@\\[\\]]|\\\\\"|\\\\)+\\\""
+            
+            + ")@(?<domain>"
+            
+                //Hostname
+                + "[a-zA-Z0-9](?:[-a-zA-Z0-9]{0,61}[a-zA-Z0-9])?(?:\\.[a-zA-Z0-9](?:[-a-zA-Z0-9]{0,61}[a-zA-Z0-9])?)*"
+                
+                + "|"
+                
+                //IPv4
+                + "\\[(?:2(?:5[0-5]?|[0-4][0-9]?)?|[0-1][0-9]{0,2})(?:\\.(?:2(?:5[0-5]?|[0-4][0-9]?)?|[0-1][0-9]{0,2})){3}\\]"
+                
+                + "|"
+                
+                //IPv6
+                + "\\[IPv6(?::[0-9a-f]{1,4}){0,8}(?::(?::[0-9a-f]{1,4}){0,8})?\\]"
+            
+            + ")"
+            ,Pattern.CASE_INSENSITIVE
+        ).matcher("");
+
+        Set<String> emails = new TreeSet<String>();
+
+        //For each line in the input
+        for (int N = Integer.parseInt(in.nextLine()); N > 0; --N) {
+            String line = in.nextLine();
+            //Run through the regex
+            matcher.reset(line);
+            //And for each email address matched
+            while (matcher.find()) {
+                String domain = matcher.group("domain");
+                if (domain.length() < 256) {
+                    //Store in the emails list
+                    emails.add(matcher.group());
+                }
+            }
+        }
+        
+        //Print emails
+        int i = emails.size();
+        for (String email : emails) {
+            System.out.print(email + (--i > 0 ? ";" : ""));
+        }
+        in.close();
+    }
+}
diff --git a/Hackerrank/Regex/Applications/DetectHTMLLinks.java b/Hackerrank/Regex/Applications/DetectHTMLLinks.java
@@ -0,0 +1,26 @@
+import java.util.*;
+import java.util.regex.*;
+
+public class Solution {
+    public static void main(String[] args) {
+        Scanner in = new Scanner(System.in);
+        Matcher matcher = Pattern.compile(
+            "<\\s*a\\s+href\\s*=\\s*\\\""
+            + "(?<link>[^\\\\\"]*)"
+            + "\\\"[^>]*>(?:<[^>]*>)*"
+            + "(?<name>.*?)"
+            + "(?:<\\s*/[^>]*>)*<\\s*/\\s*a\\s*>",
+            Pattern.CASE_INSENSITIVE
+        ).matcher("");
+        
+        for (int N = Integer.parseInt(in.nextLine()); N > 0; N--) {
+            String html = in.nextLine();
+            matcher.reset(html);
+            while (matcher.find()) {
+                String link = matcher.group("link").trim();
+                String name = matcher.group("name").trim();
+                System.out.println(link+","+name);
+            }
+        }
+    }
+}
diff --git a/Hackerrank/Regex/Applications/DetectHTMLTags.java b/Hackerrank/Regex/Applications/DetectHTMLTags.java
@@ -0,0 +1,47 @@
+import java.io.*;
+import java.util.*;
+import java.util.regex.*;
+
+public class Solution {
+
+    public static void main(String[] args) throws IOException{
+        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
+        Set<String> set = new TreeSet<String>();
+        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
+        Matcher m = Pattern.compile(
+            
+            //Opening bracket and optional spaces
+            "<\\s*"
+            //Tag name
+            + "([a-z0-9]+)"
+            
+            //Optional 1+ spaces and tag attributes
+            +"(?:\\s(?:\\s*[a-z]+\\s*=\\s*\\\"[^\\\\\"]*\\\")*)?"
+            
+            //Self-close tag or normal tag
+            +"\\s*(?:\\/>|>)",
+            
+            //Input is valid html so assume 
+            //existence closing tags and correct nesting
+            
+            Pattern.CASE_INSENSITIVE
+        ).matcher("");
+        
+        //Find all the tags in input
+        int N = Integer.parseInt(reader.readLine());
+        while (N-- > 0) {
+            String line = reader.readLine();
+            m.reset(line);
+            while (m.find()) {
+                set.add(m.group(1));
+            }
+        }
+
+        //Print out tags
+        int count = 0;
+        int size = set.size();
+        for (String word : set) {
+            System.out.print((++count < size) ? word + ";" : word);
+        }
+    }
+}
diff --git a/Hackerrank/Regex/Applications/DetectLatLon.java b/Hackerrank/Regex/Applications/DetectLatLon.java
@@ -0,0 +1,22 @@
+import java.io.*;
+import java.util.regex.*;
+public class Solution {
+    public static void main(String[] args) throws IOException {
+        StringBuffer sb = new StringBuffer();
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        Matcher matcher = Pattern.compile(
+            "^\\("
+            //Latitude
+            + "[-+]?(?:90(?:\\.0+)?|[1-8]?[0-9](?:\\.[0-9]+)?)"
+            + ", "
+            //Longitude
+            + "[-+]?(?:180(?:\\.0+)?|(?:(?:[0-9]?[0-9]|1[0-7][0-9])(?:\\.[0-9]+)?))"
+            + "\\)$"
+        ).matcher("");
+        for(byte N = Byte.parseByte(br.readLine()); N > 0; --N){
+            matcher.reset(br.readLine());
+            sb.append(matcher.matches() ? "Valid\n" : "Invalid\n");
+        }
+        System.out.print(sb);
+    }
+}
diff --git a/Hackerrank/Regex/Applications/FindAWord.java b/Hackerrank/Regex/Applications/FindAWord.java
@@ -0,0 +1,32 @@
+import java.io.*;
+import java.util.*;
+import java.util.regex.*;
+public class Solution {
+
+    public static void main(String[] args) throws IOException{
+        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
+         Map<String, Integer> map = new HashMap<String, Integer>();
+        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
+        Matcher m = Pattern.compile(
+            "(?<![_0-9a-z])[_0-9a-z]+(?![_0-9a-z])", 
+            Pattern.CASE_INSENSITIVE
+        ).matcher("");
+        int N = Integer.parseInt(reader.readLine());
+        while (N-- > 0) {
+            String line = reader.readLine();
+            m.reset(line);
+            while (m.find()) {
+                String word = m.group();
+                Integer count = map.get(word);
+                map.put(word, (count == null) ? 1 : count+1);
+            }
+        }
+        int T = Integer.parseInt(reader.readLine());
+        while (T-- > 0) {
+            String word = reader.readLine();
+            Integer count = map.get(word);
+            System.out.println((count == null) ? 0 : count);
+        }
+        reader.close();
+    }
+}
diff --git a/Hackerrank/Regex/Applications/HackerrankTweets.java b/Hackerrank/Regex/Applications/HackerrankTweets.java
@@ -0,0 +1,22 @@
+import java.io.*;
+import java.util.*;
+import java.util.regex.*;
+
+public class Solution {
+
+    public static void main(String[] args) throws IOException {
+        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
+        final String KEY = "hackerrank";
+        Scanner in = new Scanner(System.in);
+        Matcher matcher = Pattern.compile(KEY, Pattern.CASE_INSENSITIVE).matcher("");
+        //Count the tweets with KEY in it
+        int count = 0;
+        for(int N = Integer.parseInt(in.nextLine()); N > 0; --N) {
+            String tweet = in.nextLine();
+            matcher.reset(tweet);
+            count += matcher.find() ? 1 : 0;
+        }
+        //Output count
+        System.out.println(count);
+    }
+}
diff --git a/Hackerrank/Regex/Applications/IDEComments.java b/Hackerrank/Regex/Applications/IDEComments.java
diff --git a/Hackerrank/Regex/Applications/IPAddressValidation.java b/Hackerrank/Regex/Applications/IPAddressValidation.java
@@ -0,0 +1,34 @@
+import java.io.*;
+import java.util.*;
+import java.util.regex.*;   
+
+public class Solution {
+
+    public static void main(String[] args) throws IOException{
+        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
+         BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
+        Matcher IPv4Matcher = Pattern.compile(
+            "(?:2(?:5[0-5]?|[0-4][0-9]?|[0-9])?|[0-1][0-9]{0,2}|[3-9][0-9]?)(?:\\.(?:2(?:5[0-5]?|[0-4][0-9]?|[0-9])?|[0-1][0-9]{0,2}|[3-9][0-9]?)){3}"
+        ).matcher("");
+        Matcher IPv6Matcher = Pattern.compile(
+            "[0-9a-f]{1,4}(?::[0-9a-f]{1,4}){7}",
+            Pattern.CASE_INSENSITIVE
+        ).matcher("");
+        int N = Integer.parseInt(reader.readLine());
+         while (N-- > 0) {
+            String address = reader.readLine().trim();
+            IPv4Matcher.reset(address);
+            if (IPv4Matcher.matches()) {
+                System.out.println("IPv4");
+                continue;
+            }
+            IPv6Matcher.reset(address);
+            if (IPv6Matcher.matches()) {
+                System.out.println("IPv6");
+                continue;
+            }
+            System.out.println("Neither");
+        }
+        reader.close();
+    }
+}
diff --git a/Hackerrank/Regex/Applications/ValidPANFormat.java b/Hackerrank/Regex/Applications/ValidPANFormat.java
@@ -0,0 +1,19 @@
+import java.io.*;
+import java.util.*;
+import java.util.regex.*;
+public class Solution {
+
+    public static void main(String[] args) throws IOException{
+        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
+        StringBuffer sb = new StringBuffer();
+        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
+        Matcher m = Pattern.compile("^[A-Z]{5}[0-9]{4}[A-Z]$").matcher("");
+        int N = Integer.parseInt(reader.readLine());
+        while (N-- > 0) {
+            String line = reader.readLine();
+            String output = m.reset(line).matches() ? "YES\n" : "NO\n";
+            sb.append(output);
+        }
+        System.out.print(sb);
+    }
+}
