Add Transpose Matrix in Java (issue #3353)

archive/j/java/TransposeMatrix.java

@@ -0,0 +1,69 @@
+import java.util.*;
+
+public class TransposeMatrix {
+    private static final int MAX_MATRIX_SIZE = 100;
+    private static final String USAGE_MSG = "Usage: please enter the dimension of the matrix and the serialized matrix";
+
+    public static void transposeMatrix(int[] matrix, int rows, int cols, int[] transposed) {
+        for (int i = 0; i < rows; i++) {
+            for (int j = 0; j < cols; j++) {
+                transposed[j * rows + i] = matrix[i * cols + j];
+            }
+        }
+    }
+
+    public static void main(String[] args) {
+        if (args.length != 3) {
+            System.out.println(USAGE_MSG);
+            return;
+        }
+
+        int cols, rows;
+        String input = args[2];
+
+        try {
+            cols = Integer.parseInt(args[0]);
+            rows = Integer.parseInt(args[1]);
+        } catch (Exception e) {
+            System.out.println(USAGE_MSG);
+            return;
+        }
+
+        if (cols <= 0 || rows <= 0 || input.isEmpty()) {
+            System.out.println(USAGE_MSG);
+            return;
+        }
+
+        int[] matrix = new int[MAX_MATRIX_SIZE];
+        int[] transposed = new int[MAX_MATRIX_SIZE];
+        int count = 0;
+
+        String[] tokens = input.split(",");
+        for (String token : tokens) {
+            if (count >= rows * cols) break;
+
+            token = token.trim();
+            try {
+                matrix[count++] = Integer.parseInt(token);
+            } catch (Exception e) {
+                System.out.println(USAGE_MSG);
+                return;
+            }
+        }
+
+        if (count != rows * cols) {
+            System.out.println(USAGE_MSG);
+            return;
+        }
+
+        transposeMatrix(matrix, rows, cols, transposed);
+
+        for (int i = 0; i < cols * rows; i++) {
+            System.out.print(transposed[i]);
+            if (i < cols * rows - 1) {
+                System.out.print(", ");
+            }
+        }
+        System.out.println();
+    }
+}