update 713

Author: fishercoder1534

Diff for: src/main/java/com/fishercoder/solutions/firstthousand/_713.java

@@ -2,18 +2,22 @@
 
 public class _713 {
     public static class Solution1 {
+        /**
+         * Classic two pointer technique, in this problem:
+         * the right pointer keeps moving forward and the left pointer moves forward when the current product >= k
+         */
         public int numSubarrayProductLessThanK(int[] nums, int k) {
             if (k < 2) {
                 return 0;
             }
             int result = 0;
             int product = 1;
-            for (int i = 0, right = 0; right < nums.length; right++) {
+            for (int left = 0, right = 0; right < nums.length; right++) {
                 product *= nums[right];
-                while (i < nums.length && product >= k) {
-                    product /= nums[i++];
+                while (left < nums.length && product >= k) {
+                    product /= nums[left++];
                 }
-                result += right - i + 1;
+                result += right - left + 1;
             }
             return result;
         }

Diff for: src/test/java/com/fishercoder/firstthousand/_713Test.java

@@ -1,18 +1,18 @@
 package com.fishercoder.firstthousand;
 
 import com.fishercoder.solutions.firstthousand._713;
-import org.junit.BeforeClass;
-import org.junit.Test;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 public class _713Test {
     private static _713.Solution1 solution1;
     private static int[] nums;
     private static int k;
 
-    @BeforeClass
-    public static void setup() {
+    @BeforeEach
+    public void setup() {
         solution1 = new _713.Solution1();
     }