ht Diana

src/main/java/school/lemon/changerequest/java/introduction/hw2/Task1.java

@@ -1,7 +1,13 @@
 package school.lemon.changerequest.java.introduction.hw2;
 
+import java.util.Formatter;
+
 public class Task1 {
     public static String makeTags(String tag, String text) {
-        return "";
+
+
+        return String.format("%s", "<" + tag + ">"
+                + text + "</" + tag + ">");
+
     }
 }

src/main/java/school/lemon/changerequest/java/introduction/hw2/Task10.java

@@ -1,7 +1,23 @@
 package school.lemon.changerequest.java.introduction.hw2;
 
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 public class Task10 {
     public static String trim(String text) {
+        if (text == null) {
+            return null;
+        }
+        //               ""
+        String stext = "(((?<=[\\s])[\\w]+.*[^\\s]+)|([\\w]).*[^\\s])";
+
+
+        Pattern ptext = Pattern.compile(stext);
+        Matcher mtext = ptext.matcher(text);
+        StringBuilder surl = new StringBuilder();
+        if (mtext.find()) {
+            return mtext.group();
+        }
         return "";
     }
 }

src/main/java/school/lemon/changerequest/java/introduction/hw2/Task2.java

@@ -3,6 +3,13 @@
 
 public class Task2 {
     public static String firstTwo(String s) {
-        return "";
+
+
+        if (s == null || s.length() < 2)
+            return s;
+
+        return s.substring(0, 2);
+
+
     }
 }

src/main/java/school/lemon/changerequest/java/introduction/hw2/Task3.java

@@ -3,6 +3,23 @@
 
 public class Task3 {
     public static String comboString(String s1, String s2) {
-        return "";
+
+
+        if (s1 == null)
+
+            return null + s2 + null;
+
+        else if (s2 == null)
+            return null + s1 + null;
+
+
+        if (s1.length() > s2.length())
+            return s2 + s1 + s2;
+
+
+        else return s1 + s2 + s1;
+
+
+
     }
 }

src/main/java/school/lemon/changerequest/java/introduction/hw2/Task4.java

@@ -2,6 +2,26 @@
 
 public class Task4 {
     public static String charAt(String s, int i) {
-        return "";
+
+
+        if (i < 0 && Math.abs(i) <= s.length()) {
+            StringBuilder s1 = new StringBuilder(s);
+            s1.reverse();
+            i = Math.abs(i) - 1;
+            return String.valueOf(s1.charAt(i));
+        }
+
+
+        if (i < 0 && Math.abs(i) > s.length()) {
+            StringBuilder s1 = new StringBuilder(s);
+            s1.reverse();
+            i = s.length() - (Math.abs(i) - 1);
+            return String.valueOf(s1.charAt(i));
+        }
+
+        if (i > 0 && i >= s.length()) {
+            i = i - s.length();
+        }
+        return String.valueOf(s.charAt(i));
     }
 }

src/main/java/school/lemon/changerequest/java/introduction/hw2/Task5.java

@@ -2,6 +2,10 @@
 
 public class Task5 {
     public static boolean commondEnd(int[] a, int[] b) {
-        return false;
+
+
+        return (a[0] == b[0] || a[0] == b[b.length - 1] || a[a.length - 1] == b[0] || a[a.length - 1] == b[b.length - 1]);
+
+
     }
 }

src/main/java/school/lemon/changerequest/java/introduction/hw2/Task6.java

@@ -1,8 +1,17 @@
 package school.lemon.changerequest.java.introduction.hw2;
 
 
+
+
 public class Task6 {
     public static int[] reverse(int[] arr) {
-        return null;
+        if (arr == null) {
+            return null;
+        }
+        int reverseArr[] = new int[arr.length];
+        for (int i = arr.length - 1, n = 0; i >= 0 && n < arr.length; i--, n++) {
+            reverseArr[i] = arr[n];
+        }
+        return reverseArr;
     }
 }

src/main/java/school/lemon/changerequest/java/introduction/hw2/Task7.java

@@ -2,6 +2,14 @@
 
 public class Task7 {
     public static int countEvens(int[] arr) {
-        return 0;
+        if (arr == null) {
+            return 0;
+        }
+        int n = 0;
+        for (int i = arr.length - 1; i >= 0; --i)
+            if (arr[i] % 2 == 0) {
+                n++;
+            }
+        return n;
     }
 }

src/main/java/school/lemon/changerequest/java/introduction/hw2/Task8.java

@@ -3,6 +3,23 @@
 public class Task8 {
 
     public static int[] evenOdd(int[] arr) {
-        return null;
+        if (arr == null) {
+            return null;
+        }
+        int newArr[] = new int[arr.length];
+        int n = 0;
+        for (int i = 0; i < arr.length; i++) {
+            {
+                if (arr[i] % 2 == 0)
+                    newArr[n++] = arr[i];
+            }
+        }
+        for (int i = 0, m = 0; i < arr.length; i++) {
+            {
+                if (arr[i] % 2 != 0)
+                    newArr[n + m++] = arr[i];
+            }
+        }
+        return newArr;
     }
 }

src/main/java/school/lemon/changerequest/java/introduction/hw2/Task9.java

@@ -1,7 +1,27 @@
 package school.lemon.changerequest.java.introduction.hw2;
 
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 public class Task9 {
     public static String[] extractData(String URL) {
+        if (URL == null) {
+            return new String[]{"", "", ""};
+        }
+
+
+
+String url =" ( (?<=\\:\\/\\/) [\\w] +.) ? ((?<= \\/\\/) [\\w\\d.-_] +.) ((?<=\\: ) [\\d] ) ";
+        Pattern purl = Pattern.compile(url);
+        Matcher murl = purl.matcher(URL);
+        StringBuilder surl = new StringBuilder();
+        if (murl.find()){
+           surl.append(murl.group()).append("\n");
+        return new String[]{surl.toString()};
+        }
+
+
         return new String[]{"", "", ""};
+
     }
 }