style: enable HideUtilityClassConstructor in checkstyle (#5147)

src/main/java/com/thealgorithms/misc/Sparsity.java

@@ -0,0 +1,56 @@
+package com.thealgorithms.misc;
+
+import java.util.Scanner;
+
+/*
+ *A matrix is sparse if many of its coefficients are zero (In general if 2/3rd of matrix elements
+ *are 0, it is considered as sparse). The interest in sparsity arises because its exploitation can
+ *lead to enormous computational savings and because many large matrix problems that occur in
+ *practice are sparse.
+ *
+ * @author Ojasva Jain
+ */
+
+final class Sparsity {
+    private Sparsity() {
+    }
+
+    /*
+     * @return Sparsity of matrix
+     *
+     * where sparsity = number of zeroes/total elements in matrix
+     *
+     */
+    static double sparsity(double[][] mat) {
+        int zero = 0;
+        // Traversing the matrix to count number of zeroes
+        for (int i = 0; i < mat.length; i++) {
+            for (int j = 0; j < mat[i].length; j++) {
+                if (mat[i][j] == 0) {
+                    zero++;
+                }
+            }
+        }
+        // return sparsity
+        return ((double) zero / (mat.length * mat[1].length));
+    }
+
+    // Driver method
+    public static void main(String[] args) {
+        Scanner in = new Scanner(System.in);
+        System.out.println("Enter number of rows in matrix: ");
+        int n = in.nextInt();
+        System.out.println("Enter number of Columns in matrix: ");
+        int m = in.nextInt();
+
+        System.out.println("Enter Matrix elements: ");
+        double[][] mat = new double[n][m];
+        for (int i = 0; i < n; i++) {
+            for (int j = 0; j < m; j++) {
+                mat[i][j] = in.nextDouble();
+            }
+        }
+        System.out.println("Sparsity of matrix is: " + sparsity(mat));
+        in.close();
+    }
+}