feat: Matrix rotation 90' anti-clock direction

2D_Array/readme.md

@@ -17,6 +17,7 @@ Due to the fact that the elements of 2D arrays can be random accessed. Similar t
 * Multiplication of two Matrices ----> [Java](/Code/Java/matrixop_mul.java)
 * Overall Median of Matrix ---> [Java](/Code/Java/overall_median_matrix.java)
 * Row-wise sum ----> [C++](/Code/C++/row_wise_sum.cpp) | [java](/Code/java/RowWise_Sum.java)
+* Rotate Matrix 90' Anti-Clockwise without extra space  ----> [C++](/Code/C++/RotateMatrixBy90.cpp)
 * Spiral Print ----> [C++](/Code/C++/spiral_print.cpp)
 * Staircase Search ----> [C++](/Code/C++/staircase_search.cpp)
 * Substraction of two Matrices ----> [Java](/Code/Java/matrixop_sub.java)

Code/C++/RotateMatrixBy90.cpp

@@ -0,0 +1,83 @@
+#include<iostream> // for `i/o operation`
+#define N 3 // defining size `N`
+
+/*
+function to swap values of two valiables
+*/
+void swap(int &num1, int &num2){
+    int temp = num1;
+    num1 = num2;
+    num2 = temp;
+}
+
+/*
+function to print the matrix in matrix form
+*/
+void printMatrix(int matrix[N][N]){
+    for(int i = 0; i < N; i++){
+        for(int j = 0; j < N; j++){
+            std::cout<< "["<< matrix[i][j]<< "]\t";
+        }
+        std::cout<< std::endl;
+    }
+}
+
+/*
+main function or the driver function
+*/
+int main(){
+    /* ###Test Case: 01
+    Matrix:
+        1 2 3
+        4 5 6
+        7 8 9
+    After Rotation:
+        3 6 9
+        2 5 6
+        7 8 9
+    */
+    /* ###Test Case: 02
+    Matrix:
+        10 9 4
+        3 4 20
+        50 12 19
+    After Rotation:
+        4 20 19
+        9 4 12
+        10 3 50
+    */
+
+    // Initializing matrix
+    int matrix[N][N] = {
+                        {1, 2, 3},
+                        {4, 5, 6},
+                        {7, 8, 9}
+                    };
+    std::cout<< "\nInitial Matrix Is: "<< std::endl;
+    printMatrix(matrix);
+
+    for(int i = 0; i < N; i++){
+        for(int j = i; j < N; j++){
+            swap(matrix[i][j], matrix[j][i]);
+        }
+    }
+    // std::cout<< "\nTranspose Of Matrix Is: "<< std::endl;
+    // printMatrix(matrix);
+
+    for(int i = 0; i < N; i++){
+        int start = 0, end = N-1;
+
+        while(start < end){
+            swap(matrix[start][i], matrix[end][i]);
+            start += 1;
+            end -= 1;
+        }
+    }
+    std::cout<< "\n90` Rotation Of Matrix Is: "<< std::endl;
+    printMatrix(matrix);
+
+    return 0;
+}
+
+// Time Complexity: O(N*N), Where 'N' is the size of square matrix
+// Auxiliary Space: O(1), No extra space has been used