HomeWork2:Tasks(1-3,5-7)

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

@@ -1,7 +1,8 @@
 package school.lemon.changerequest.java.introduction.hw2;
 
 public class Task1 {
-    public static String makeTags(String tag, String text) {
-        return "";
+    public static String makeTags(String tag, String text)
+    {
+        return String.format("%1$s%2$s%3$s%4$s%5$s%2$s%3$s", "<", tag, ">", text, "</", tag, ">");
     }
 }

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

@@ -3,6 +3,14 @@
 
 public class Task2 {
     public static String firstTwo(String s) {
-        return "";
+        if (s == null)
+            return null;
+        else if (s.equals(""))
+            return "";
+        else
+            if (s.length() <= 2) {
+                return s;
+            }
+        return s.substring(0, 2);
     }
 }

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

@@ -2,7 +2,17 @@
 
 
 public class Task3 {
-    public static String comboString(String s1, String s2) {
-        return "";
+    public static String comboString(String s1, String s2)
+    {
+        if(s1 == null)
+            return s1+s2+s1;
+        else
+        if(s2 == null)
+            return s2 + s1 + s2;
+        else
+        if(s1.length() < s2.length())
+            return s1+s2+s1;
+
+                return s2+s1+s2;
     }
 }

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

@@ -2,6 +2,7 @@
 
 public class Task5 {
     public static boolean commondEnd(int[] a, int[] b) {
-        return false;
+        return (a[0] == b[0] || a[a.length-1] == b[b.length-1] || a[0] == b[b.length-1] || a[a.length-1] == b[0]);
+
     }
 }

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

@@ -3,6 +3,15 @@
 
 public class Task6 {
     public static int[] reverse(int[] arr) {
-        return null;
+        if (arr == null) {
+            return null;
+        }
+        int[]a = new int[arr.length];
+        for(int i = 0;i < arr.length;i++)
+        {
+            a[arr.length-1-i] = arr[i];
+
+        }
+        return a;
     }
 }

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

@@ -2,6 +2,15 @@
 
 public class Task7 {
     public static int countEvens(int[] arr) {
-        return 0;
+        int count=0;
+        if(arr == null)
+            return 0;
+        for (int anArr : arr) {
+            boolean b = anArr % 2 == 0;
+            if (b)
+                count++;
+
+        }
+        return count;
     }
 }