add LazerBeam solution

Author: jakovmitrovski

medium300/LaserBeam.java

@@ -0,0 +1,23 @@
+package medium300;
+
+public class LaserBeam {
+
+    int gcd(int a, int b) {
+        if (b == 0)
+            return a;
+        return gcd(b, a % b);
+    }
+
+    public int calculateNumberOfEnteredCells(int x1, int y1, int x2, int y2) {
+
+        int a = Math.abs(x1 - x2);
+        int b = Math.abs(y1 - y2);
+
+        return a + b - gcd(Math.max(a, b), Math.min(a, b));
+    }
+
+    public static void main(String[] args) {
+        LaserBeam l = new LaserBeam();
+        System.out.println(l.calculateNumberOfEnteredCells(9333, 3923, 63958, 10065));
+    }
+}