feat(leetcode): add No.3028

Author: mickey0524

3028.Ant-on-the-Boundary.java

@@ -0,0 +1,25 @@
+// https://leetcode.com/problems/ant-on-the-boundary/description/
+// algorithms
+// Easy (75.0%)
+// Total Accepted: 37.5K
+// Total Submissions: 49.9K
+
+
+class Solution {
+
+    public int returnToBoundaryCount(int[] nums) {
+        int curPosition = 0;
+        int res = 0;
+
+        for (int n : nums) {
+            curPosition += n;
+
+            if (curPosition == 0) {
+                res += 1;
+            }
+        }
+
+        return res;
+    }
+
+}