Added MirrorOfMatrix.java (#4461)

* Added MirrorOfMatrix.java * Fixing Linting Issue * Fixing Linting Issue * Fixing Linting Issue * Fixing Linting Issue * Fixing Linting Issue * Fixing Linting Issue * Fixing Linting Issue * Fixing Linting Issue * Changes Done * Update src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Changes Done * Added MirrorOfMatrixTest.java * Added MirrorOfMatrixTest.java * Linting Error in Test * Linting Error in Test * Linting Error in Test * trying to fix build error * trying to fix build error * final * Update src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Update src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Update src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Update src/test/java/com/thealgorithms/misc/MirrorOfMatrixTest.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Update src/test/java/com/thealgorithms/misc/MirrorOfMatrixTest.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Update src/test/java/com/thealgorithms/misc/MirrorOfMatrixTest.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Changing Description * Final * Update src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Final * Update src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Changes * Changes * Linting Issue * Linting Issue * Linting Issue * Changes * Fixing Minor Linting Issue * Fixing Minor Linting Issue * Final * Update src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Changes * Linting Issue * Linting Issue * Linting Issue * Linting Issue * Update src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Update src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Update src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> * Changes * Changes * fix: use proper size in `checkInput` * style: basic linting --------- Co-authored-by: Piotr Idzik <65706193+vil02@users.noreply.github.com> Co-authored-by: vil02 <vil02@o2.pl>
2023-10-03 22:12:56 +05:30 · 2023-10-03 22:12:56 +05:30 · 329cc3bcf9
commit 329cc3bcf9
parent 9795bada90
2 changed files with 110 additions and 0 deletions
--- a/src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java
+++ b/src/main/java/com/thealgorithms/misc/MirrorOfMatrix.java
@ -0,0 +1,57 @@
+package com.thealgorithms.misc;
+
+// Problem Statement
+/*
+We have given an array of m x n (where m is the number of rows and n is the number of columns).
+Print the new matrix in such a way that the new matrix is the mirror image of the original matrix.
+
+The Original matrix is:   |   The Mirror matrix is:
+1	2	3	              |   3	 2	 1
+4	5	6	              |   6	 5	 4
+7	8	9	              |   9	 8	 7
+
+@author - Aman (https://github.com/Aman28801)
+*/
+
+public final class MirrorOfMatrix {
+    private MirrorOfMatrix() {
+    }
+
+    public static int[][] mirrorMatrix(final int[][] originalMatrix) {
+        if (originalMatrix == null) {
+            // Handle invalid input
+            return null;
+        }
+        if (originalMatrix.length == 0) {
+            return new int[0][0];
+        }
+
+        checkInput(originalMatrix);
+
+        int numRows = originalMatrix.length;
+        int numCols = originalMatrix[0].length;
+
+        int[][] mirroredMatrix = new int[numRows][numCols];
+
+        for (int i = 0; i < numRows; i++) {
+            mirroredMatrix[i] = reverseRow(originalMatrix[i]);
+        }
+        return mirroredMatrix;
+    }
+    private static int[] reverseRow(final int[] inRow) {
+        int[] res = new int[inRow.length];
+        for (int i = 0; i < inRow.length; ++i) {
+            res[i] = inRow[inRow.length - 1 - i];
+        }
+        return res;
+    }
+
+    private static void checkInput(final int[][] matrix) {
+        // Check if all rows have the same number of columns
+        for (int i = 1; i < matrix.length; i++) {
+            if (matrix[i].length != matrix[0].length) {
+                throw new IllegalArgumentException("The input is not a matrix.");
+            }
+        }
+    }
+}
--- a/src/test/java/com/thealgorithms/misc/MirrorOfMatrixTest.java
+++ b/src/test/java/com/thealgorithms/misc/MirrorOfMatrixTest.java
@ -0,0 +1,53 @@
+package com.thealgorithms.misc;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import org.junit.jupiter.api.Test;
+
+class MirrorOfMatrixTest {
+
+    @Test
+    void testMirrorMatrixRegularMatrix() {
+        int[][] originalMatrix = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
+        int[][] expectedMirrorMatrix = {{3, 2, 1}, {6, 5, 4}, {9, 8, 7}};
+        int[][] mirroredMatrix = MirrorOfMatrix.mirrorMatrix(originalMatrix);
+        assertArrayEquals(expectedMirrorMatrix, mirroredMatrix);
+    }
+
+    @Test
+    void testMirrorMatrixEmptyMatrix() {
+        int[][] originalMatrix = {};
+        int[][] expectedMirrorMatrix = {};
+        int[][] mirroredMatrix = MirrorOfMatrix.mirrorMatrix(originalMatrix);
+        assertArrayEquals(expectedMirrorMatrix, mirroredMatrix);
+    }
+
+    @Test
+    void testMirrorMatrixSingleElementMatrix() {
+        int[][] originalMatrix = {{42}};
+        int[][] expectedMirrorMatrix = {{42}};
+        int[][] mirroredMatrix = MirrorOfMatrix.mirrorMatrix(originalMatrix);
+        assertArrayEquals(expectedMirrorMatrix, mirroredMatrix);
+    }
+
+    @Test
+    void testMirrorMatrixMultipleRowsOneColumnMatrix() {
+        int[][] originalMatrix = {{1}, {2}, {3}, {4}};
+        int[][] expectedMirrorMatrix = {{1}, {2}, {3}, {4}};
+        int[][] mirroredMatrix = MirrorOfMatrix.mirrorMatrix(originalMatrix);
+        assertArrayEquals(expectedMirrorMatrix, mirroredMatrix);
+    }
+
+    @Test
+    void testMirrorMatrixNullInput() {
+        int[][] originalMatrix = null;
+        assertNull(MirrorOfMatrix.mirrorMatrix(originalMatrix));
+    }
+
+    @Test
+    void testMirrotMarixThrows() {
+        assertThrows(IllegalArgumentException.class, () -> MirrorOfMatrix.mirrorMatrix(new int[][] {{1}, {2, 3}}));
+    }
+}