Merge remote-tracking branch 'origin/master'

This reverts commit 29e63163a4.

src/Lab2.java

@@ -3,7 +3,7 @@ public class Lab2 {
         final int A = 2;
         final int[][] MATRIX_B = {
                 {1, 202, 1, 1, 202, 3, 1, 202, 3,},
-                {1, 202, 1, 1, 202, 3, 1, 202, 3,},
+                {1, 202, 1, 1, 202, 3, 1, 202, 3, 4},
                 {1, 1,   3, 1, 202, 3, 1, 202, 3,},
 //                {4, 5, 6,},
         };
@@ -12,7 +12,15 @@ public class Lab2 {
 
         print(MATRIX_C);
 
-        System.out.println("Sum of smallest elements in every column: " + sumOfSmallestElementsInEveryColumn(MATRIX_C));
+//        System.out.println("Sum of smallest elements in every column: " + sumOfSmallestElementsInEveryColumn(MATRIX_C));
+        try {
+            System.out.println("Sum of smallest elements in every column: " + sumOfSmallestElementsInEveryColumnRenew(MATRIX_C));
+            System.out.println("???...");
+        } catch (Exception e) {
+            System.err.println(e.getMessage());
+        }
+
+        System.out.println("I'm still working...");
 
         /*int[] array = {1, 2, 3};
         int[] array2 = new int[3];
@@ -78,6 +86,36 @@ public class Lab2 {
         return sum;
     }
 
+    private static int sumOfSmallestElementsInEveryColumnRenew(final int[][] MATRIX_C) throws Exception {
+//        todo check different length of rows
+        for (int i = 1; i < MATRIX_C.length; i++) {
+            if (MATRIX_C[i].length != MATRIX_C[0].length) {
+                throw new /*Runtime*/Exception("There are different lengths of matrix rows.");
+//                System.err.println("There are different lengths of matrix rows.");
+//                System.exit(0);
+            }
+        }
+        int sum = 0;
+        for (int j = 0; j < MATRIX_C[0].length; j++) {
+            int tmpSmallest = MATRIX_C[0][j];
+            boolean valueRepeats = false;
+            for (int i = 1; i < MATRIX_C.length; i++) {
+                if (MATRIX_C[i][j] < tmpSmallest) {
+                    tmpSmallest = MATRIX_C[i][j];
+                    valueRepeats = false;
+                } else if (MATRIX_C[i][j] == tmpSmallest) {
+                    valueRepeats = true;
+                }
+            }
+            sum += tmpSmallest;
+
+            if (!valueRepeats) {
+                sum += tmpSmallest;
+            }
+        }
+        return sum;
+    }
+
     private static void print(final int[][] MATRIX_C) {
         for (int i = 0; i < MATRIX_C.length; i++) {
             for (int j = 0; j < MATRIX_C[i].length; j++) {

src/Lab3.java

@@ -0,0 +1,73 @@
+public class Lab3 {
+    private static final int REPETITION_NUMBER = 10;
+    public static void main(String[] args) {
+        StringBuilder result = new StringBuilder();
+        for (int i = 0; i < REPETITION_NUMBER; i++) {
+//            result += Integer.toString(i);
+//            result += String.valueOf(i);
+            result.append(i);
+        }
+
+
+
+        /*float f = 1.1f;
+        double d = 2.2;
+//        f = (float) (f + d);
+        f += d;*/
+
+        String s = "ASD";
+
+        StringBuilder stringBuilder = new StringBuilder("ASD");
+        StringBuffer stringBuffer = new StringBuffer("ASD");
+
+        stringBuilder.append("A");
+        System.out.println(s.length());
+        System.out.println(stringBuilder.length());
+        System.out.println(stringBuffer.length());
+
+        System.out.println(s.endsWith("D"));
+//        System.out.println(stringBuilder.substring(stringBuilder.length() - 1).equals("A"));
+        System.out.println("A".equals(stringBuilder.substring(stringBuilder.length() - 1)));
+        System.out.println("A".equals(stringBuffer.substring(stringBuffer.length() - 1)));
+
+        String sNull = null;
+        System.out.println("A".equals(sNull));
+        System.out.println(sNull.equals("A"));
+
+        System.out.println(s.substring(2));
+        System.out.println(s.contains("AS"));
+
+        System.out.println(s.indexOf('a'));
+
+//        System.out.println(s.charAt(-1));
+
+        System.out.println("s.equalsIgnoreCase(\"AsD\") = " + s.equalsIgnoreCase("AsD"));
+
+        String s2 = s;
+        System.out.println("s2 = " + s2);
+        System.out.println(s == s2); // true?
+        System.out.println(s.equals(s2)); // true?
+        s += "B";
+        System.out.println(s);
+        System.out.println("s2 = " + s2);
+
+        System.out.println(s == s2); // false?
+        System.out.println(s.equals(s2)); // false?
+
+        String s3 = new String("ASD");
+        System.out.println(s3 == s2); // true? (false)
+        System.out.println(s3.equals(s2)); // false? (true)
+
+//      String Pool
+        String s4 = "ASD";
+//        String s5 = new String("ASD");
+        String s5 = "AS";
+        s5 += "D";
+        System.out.println(s4 == s5); // true? (SP)
+        System.out.println(s4.equals(s5)); // (true)
+
+
+
+        System.out.println("Done!");
+    }
+}

src/lab4/Main.java

@@ -0,0 +1,7 @@
+package lab4;
+
+public class Main {
+    public static void main(String[] args) {
+        //todo equals+hashcode
+    }
+}

src/test/Test.java

@@ -0,0 +1,13 @@
+package test;
+
+public class Test {
+    public static void main(String[] args) {
+
+    }
+    static int m(){
+        System.exit(0);
+//        return 1;
+        System.out.println(123);
+        return 1;
+    }
+}

src/test/one/A.java

@@ -0,0 +1,7 @@
+package test.one;
+
+public class A implements MyMethodInterface {
+    public void myMethod() {
+
+    }
+}

src/test/one/B.java

@@ -0,0 +1,7 @@
+package test.one;
+
+public class B implements MyMethodInterface {
+    public void myMethod() {
+
+    }
+}

src/test/one/Main.java

@@ -0,0 +1,13 @@
+package test.one;
+
+public class Main {
+    public static void main(String[] args) {
+        Object[] objects = {
+                new A(),
+                new B(),
+        };
+        for (Object object : objects) {
+            ((MyMethodInterface)object).myMethod();
+        }
+    }
+}

src/test/one/MyMethodInterface.java

@@ -0,0 +1,5 @@
+package test.one;
+
+public interface MyMethodInterface {
+    void myMethod();
+}