[HackerRank][Regex](java) Applications 2

 

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■  Valid PAN format

https://www.hackerrank.com/challenges/valid-pan-format/problem?isFullScreen=true 

import java.util.*;
import java.util.regex.Pattern;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.valueOf(sc.nextLine());
        Pattern p = Pattern.compile("^[A-Z]{5}[0-9]{4}[A-Z]$");
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < n; ++i) {
            sb.append( p.matcher(sc.nextLine()).find() ? "YES\n" : "NO\n" );
        }
        sc.close();
        System.out.print(sb.toString());
    }
}

 

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■  HackerRank Language

https://www.hackerrank.com/challenges/hackerrank-language/problem?isFullScreen=true 

import java.util.*;

public class Solution {

    public static void main(String[] args) {
        String l[] = "C:CPP:JAVA:PYTHON:PERL:PHP:RUBY:CSHARP:HASKELL:CLOJURE:BASH:SCALA: ERLANG:CLISP:LUA:BRAINFUCK:JAVASCRIPT:GO:D:OCAML:R:PASCAL:SBCL:DART: GROOVY:OBJECTIVEC"
                .split(" *: *");
        List<String> ls = new ArrayList<>();
        for (String ll : l) {
            ls.add(ll);
        }
        Scanner sc = new Scanner(System.in);
        int n = Integer.valueOf(sc.nextLine());
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < n; ++i) {
            String s = sc.nextLine().toUpperCase().split(" ")[1];
            sb.append(ls.contains(s) ? "VALID\n" : "INVALID\n");
        }
        sc.close();
        System.out.print(sb.toString());
    }
}

 

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■  IP Address Validation

https://www.hackerrank.com/challenges/ip-address-validation/problem?isFullScreen=true 

import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.valueOf(sc.nextLine());
        Pattern p1 = Pattern.compile("^([0-9]{1,3})\\.([0-9]{1,3})\\.([0-9]{1,3})\\.([0-9]{1,3})$");
        Pattern p2 = Pattern.compile("^[0-9a-fA-F]{1,4}\\:[0-9a-fA-F]{1,4}\\:[0-9a-fA-F]{1,4}\\:[0-9a-fA-F]{1,4}\\:[0-9a-fA-F]{1,4}\\:[0-9a-fA-F]{1,4}\\:[0-9a-fA-F]{1,4}\\:[0-9a-fA-F]{1,4}$");
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < n; ++i) {
            String s = sc.nextLine();
            Matcher m1 = p1.matcher(s);
            Matcher m2 = p2.matcher(s);
            String r = "";
            if (m1.find()) {
                boolean v = true;
                for (int j = 1; j <= 4; ++j) {
                    int t = Integer.valueOf(m1.group(j));
                    if (t < 0 || t > 255) {
                        v = false;
                        break;
                    }
                }
                r = v ? "IPv4\n" : "Neither\n";
            } else if (m2.find()) {
                r = "IPv6\n";
            } else {
                r = "Neither\n";
            }
            sb.append(r);
        }
        sc.close();
        System.out.print(sb.toString());
    }
}

(+)

import java.util.*;
import java.util.regex.*;

public class Solution{

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.valueOf(sc.nextLine());
        Pattern p1 = Pattern.compile("(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)");
        Pattern p2 = Pattern.compile("(([0-9a-fA-F]{1,4}:){7,7}[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,7}:|([0-9a-fA-F]{1,4}:){1,6}:[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,5}(:[0-9a-fA-F]{1,4}){1,2}|([0-9a-fA-F]{1,4}:){1,4}(:[0-9a-fA-F]{1,4}){1,3}|([0-9a-fA-F]{1,4}:){1,3}(:[0-9a-fA-F]{1,4}){1,4}|([0-9a-fA-F]{1,4}:){1,2}(:[0-9a-fA-F]{1,4}){1,5}|[0-9a-fA-F]{1,4}:((:[0-9a-fA-F]{1,4}){1,6})|:((:[0-9a-fA-F]{1,4}){1,7}|:)|fe80:(:[0-9a-fA-F]{0,4}){0,4}%[0-9a-zA-Z]{1,}|::(ffff(:0{1,4}){0,1}:){0,1}((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]).){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])|([0-9a-fA-F]{1,4}:){1,4}:((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]).){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]))");
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < n; ++i) {
            String s = sc.nextLine();
            Matcher m1 = p1.matcher(s);
            Matcher m2 = p2.matcher(s);
            String r = "";
            if (m1.matches()) {
                r = "IPv4\n";
            } else if (m2.matches()) {
                r = "IPv6\n";
            } else {
                r = "Neither\n";
            }
            sb.append(r);
        }
        sc.close();
        System.out.print(sb.toString());
    }
}

( Matcher 의 find() 와 matches() 의 차이 )
 *  find() : attempts to find the next subsequence of the input sequence that matches the pattern
 *  matches() : attempts to match the entire region against the pattern

 

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■  The British and American Style of Spelling

https://www.hackerrank.com/challenges/uk-and-us/problem?isFullScreen=true 

import java.io.*;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int c = Integer.valueOf(sc.nextLine());
        String l[] = new String[c];
        for (int i = 0; i < c; ++i) {
            l[i] = sc.nextLine();
        }
        int t = Integer.valueOf(sc.nextLine());
        String w_a[] = new String[t];
        for (int i = 0; i < t; ++i) {
            w_a[i] = sc.nextLine();
        }
        sc.close();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < t; ++i) {
            int r = 0;
            String w = w_a[i];
            Pattern p = Pattern.compile( w.substring(0, w.length()-2) + "(ze|se)");
            for (int j = 0; j < c; ++j) {
                Matcher m = p.matcher(l[j]);
                while(m.find()) {
                    r++;
                }
            }
            sb.append(r+"\n");
        }
        System.out.print(sb.toString());
    }
}

 

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■  UK and US: Part 2

https://www.hackerrank.com/challenges/uk-and-us-2/problem?isFullScreen=true 

import java.util.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int c = Integer.valueOf(sc.nextLine());
        String l[] = new String[c];
        for (int i = 0; i < c; ++i) {
            l[i] = sc.nextLine();
        }
        int t = Integer.valueOf(sc.nextLine());
        String w_a[] = new String[t];
        for (int i = 0; i < t; ++i) {
            w_a[i] = sc.nextLine();
        }
        sc.close();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < t; ++i) {
            int r = 0;
            String wa = w_a[i]; // w'
            int len = wa.length();
            int idx = wa.lastIndexOf("our");
            Pattern p = Pattern.compile("(^|(?<=[\\s\\n]))" + wa.substring(0, idx) + "(our|or)" + wa.substring(idx + 3, len) + "($|(?=[\\s\\n]))");
            for (int j = 0; j < c; ++j) {
                Matcher m = p.matcher(l[j]);
                while (m.find()) {
                    r++;
                }
            }
            sb.append(r+"\n");
        }
        System.out.print(sb.toString());
    }
}

(+)

import java.util.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int c = Integer.valueOf(sc.nextLine());
        String st = "";
        for (int i = 0; i < c; ++i) {
            st += sc.nextLine() + " ";
        }
        String ss[] = st.split(" ");
        int t = Integer.valueOf(sc.nextLine());
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < t; ++i) {
            String w = sc.nextLine();
            int r = 0;
            for (String s : ss) {
                if (s.equals(w)) {
                    r++;
                }
                if (s.equals(w.replaceAll("our", "or"))) {
                    r++;
                }
            }
            sb.append(r+"\n");
        }
        sc.close();
        System.out.print(sb.toString());
    }
}

 

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■  Find A Sub-Word

https://www.hackerrank.com/challenges/find-substring/problem?isFullScreen=true 

import java.util.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.valueOf(sc.nextLine());
        String s[] = new String[n];
        for (int i = 0; i < n; ++i) {
            s[i] = sc.nextLine();
        }
        int q = Integer.valueOf(sc.nextLine());
        String w[] = new String[q];
        for (int i = 0; i < q; ++i) {
            w[i] = sc.nextLine();
        }
        sc.close();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < q; ++i) {
            int r = 0;
            Pattern p = Pattern.compile("\\w+(" + w[i] + ")\\w+");
            for (int j = 0; j < n; ++j) {
                Matcher m = p.matcher(s[j]);
                while (m.find()) {
                    r++;
                }
            }
            sb.append(r+"\n");
        }
        System.out.print(sb.toString());
    }
}

 

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■  Find a Word

https://www.hackerrank.com/challenges/find-a-word/problem?isFullScreen=true 

import java.util.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.valueOf(sc.nextLine());
        String s[] = new String[n];
        for (int i = 0; i < n; ++i) {
            s[i] = sc.nextLine();
        }
        int q = Integer.valueOf(sc.nextLine());
        String w[] = new String[q];
        for (int i = 0; i < q; ++i) {
            w[i] = sc.nextLine();
        }
        sc.close();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < q; ++i) {
            int r = 0;
            Pattern p = Pattern.compile("\\b("+ w[i] +")\\b");
            for (int j = 0; j < n; ++j) {
                Matcher m = p.matcher(s[j]);
                while (m.find()) {
                    r++;
                }
            }
            sb.append(r+"\n");
        }
        System.out.print(sb.toString());
    }
}

( 문제에서 'boundary' 라는 단어에서 힌트를 얻음 )

 

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■  Detect the Domain Name

https://www.hackerrank.com/challenges/detect-the-domain-name/problem?isFullScreen=true 

import java.util.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.valueOf(sc.nextLine());
        Pattern p = Pattern.compile("http[s]?://(ww[w2]\\.)?([a-zA-Z0-9\\-]+(\\.[a-zA-Z0-9\\-]+)+)");
        TreeSet<String> r = new TreeSet<>();
        for (int i = 0; i < n; ++i) {
            Matcher m = p.matcher(sc.nextLine());
            while (m.find()) {
                r.add(m.group(2));
            }
        }
        sc.close();
        System.out.print(String.join(";", r));
    }
}

( '\w' 는 'a to z', 'A to Z', '0 to 9' 뿐만 아니라 '_' 도 포함 )

 

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■  Detect the Email Addresses

https://www.hackerrank.com/challenges/detect-the-email-addresses/problem?isFullScreen=true 

import java.util.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.valueOf(sc.nextLine());
        Pattern p = Pattern.compile("[\\w\\.]+@\\w+(\\.\\w+)+");
        TreeSet<String> r = new TreeSet<>();
        for (int i = 0; i < n; ++i) {
            Matcher m = p.matcher(sc.nextLine());
            while (m.find()) {
                r.add(m.group());
            }
        }
        sc.close();
        System.out.print(String.join(";", r));
    }
}

( 문제에서 'There can be a number of strings separated by dots before and after the "@" symbol' )

 

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■  Detect HTML links

https://www.hackerrank.com/challenges/detect-html-links/problem?isFullScreen=true 

import java.util.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.valueOf(sc.nextLine());
        Pattern p1 = Pattern.compile("<a([^<>]*)>(.*?)</a>");	// 추출
        Pattern p2 = Pattern.compile("href=\"([^\"]*)\"");		// 추출
        Pattern p3 = Pattern.compile("<[^<>]+>");				// 제거
        List<String> r = new ArrayList<>();
        for (int i = 0; i < n; ++i) {
            String s = sc.nextLine();
            Matcher m1 = p1.matcher(s);
            while (m1.find()) {
                Matcher m2 = p2.matcher(m1.group(1));
                while (m2.find()) {
                    String s1 = m2.group(1);
                    String s2 = m1.group(2);
                    Matcher m3 = p3.matcher(s2);
                    while (m3.find()) {
                        s2 = s2.replaceAll(m3.group(), "");
                    }
                    s2 = s2.trim();
                    r.add(s1 + "," + s2);
                }
            }
        }
        sc.close();
        StringBuilder sb = new StringBuilder();
        int c = r.size();
        for (int i = 0; i < c; ++i) {
            sb.append(r.get(i) + "\n");
        }
        System.out.print(sb.toString());
    }
}

( 무조건 한꺼번에 나누려 하지 말고 부분적으로 하기 )

 

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■  Building a Smart IDE: Identifying comments

https://www.hackerrank.com/challenges/ide-identifying-comments/problem?isFullScreen=true 

import java.util.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        StringBuilder ss = new StringBuilder();
        while (sc.hasNextLine()) { // sc.hasNext()
            ss.append(sc.nextLine().trim() + "\n");
        }
        sc.close();
        String s = ss.toString();	// "//.*|(\"(?:\\[^\"]|\"|.)*?\")|(?s)/\*.*?\*/"
        Pattern p = Pattern.compile("(//.*)|(/\\*((?!\\*/).|\\s)*\\*/)");
        Matcher m = p.matcher(s);
        StringBuilder sb = new StringBuilder();
        while (m.find()) {
            sb.append(m.group() + "\n");
        }
        System.out.print(sb.toString());
    }
}

 

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■  Building a Smart IDE: Programming Language Detection

https://www.hackerrank.com/challenges/programming-language-detection/problem?isFullScreen=true 

import java.io.*;
import java.util.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        StringBuilder ss = new StringBuilder();
        while (sc.hasNextLine()) { // sc.hasNext()
            ss.append(sc.nextLine() + "\n");
        }
        sc.close();
        String s = ss.toString().replaceAll("(\\/\\/.*)|(\\/\\*((?!\\*\\/).|\\s)*\\*\\/)|(#(?!include|define).*)", "");
        String [] nm_arr = {"Java", "C", "Python"};
        String [] p_arr = {"\\bSystem\\.(out|err)\\.print(f|ln*)\\(", "\\s+printf\\(", "\\bprint[\\(| ]"};
        int n = nm_arr.length;
        loop:
        for (int i = 0; i < n; ++i) {
            Pattern p = Pattern.compile(p_arr[i]);
            Matcher m = p.matcher(s);
            while (m.find()) {
                System.out.println(nm_arr[i]);
                break loop;
            }
        }
    }
}

 

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