Change project structure to a Maven Java project + Refactor (#2816)

src/main/java/com/thealgorithms/others/GuassLegendre.java

@@ -0,0 +1,43 @@
+package com.thealgorithms.others;
+
+/**
+ * Guass Legendre Algorithm ref
+ * https://en.wikipedia.org/wiki/Gauss–Legendre_algorithm
+ *
+ * @author AKS1996
+ */
+public class GuassLegendre {
+
+    public static void main(String[] args) {
+        for (int i = 1; i <= 3; ++i) {
+            System.out.println(pi(i));
+        }
+    }
+
+    static double pi(int l) {
+        /*
+     * l: No of loops to run
+         */
+
+        double a = 1, b = Math.pow(2, -0.5), t = 0.25, p = 1;
+        for (int i = 0; i < l; ++i) {
+            double temp[] = update(a, b, t, p);
+            a = temp[0];
+            b = temp[1];
+            t = temp[2];
+            p = temp[3];
+        }
+
+        return Math.pow(a + b, 2) / (4 * t);
+    }
+
+    static double[] update(double a, double b, double t, double p) {
+        double values[] = new double[4];
+        values[0] = (a + b) / 2;
+        values[1] = Math.sqrt(a * b);
+        values[2] = t - p * Math.pow(a - values[0], 2);
+        values[3] = 2 * p;
+
+        return values;
+    }
+}