add 2090

fishercoder1534 · fishercoder1534 · commit 5e8f1e5844cd · 2021-11-27T20:10:44.000-08:00
diff --git a/README.md b/README.md
@@ -8,6 +8,7 @@ _If you like this project, please leave me a star._ &#9733;
 
 |  #  |      Title     |   Solutions   | Video  | Difficulty  | Tag                  
 |-----|----------------|---------------|--------|-------------|-------------
+|2090|[K Radius Subarray Averages](https://leetcode.com/problems/k-radius-subarray-averages/)|[Java](../master/src/main/java/com/fishercoder/solutions/_2090.java) ||Medium||
 |2089|[Find Target Indices After Sorting Array](https://leetcode.com/problems/find-target-indices-after-sorting-array/)|[Java](../master/src/main/java/com/fishercoder/solutions/_2089.java) ||Easy||
 |2086|[Minimum Number of Buckets Required to Collect Rainwater from Houses](https://leetcode.com/problems/minimum-number-of-buckets-required-to-collect-rainwater-from-houses/)|[Java](../master/src/main/java/com/fishercoder/solutions/_2086.java) ||Medium||
 |2085|[Count Common Words With One Occurrence](https://leetcode.com/problems/count-common-words-with-one-occurrence/)|[Java](../master/src/main/java/com/fishercoder/solutions/_2085.java) ||Easy||
diff --git a/src/main/java/com/fishercoder/solutions/_2090.java b/src/main/java/com/fishercoder/solutions/_2090.java
@@ -0,0 +1,31 @@
+package com.fishercoder.solutions;
+
+public class _2090 {
+    public static class Solution1 {
+        public int[] getAverages(int[] nums, int k) {
+            if (k == 0) {
+                return nums;
+            }
+            long[] preSums = new long[nums.length];
+            preSums[0] = nums[0];
+            for (int i = 1; i < nums.length; i++) {
+                preSums[i] = preSums[i - 1] + nums[i];
+            }
+            int[] ans = new int[nums.length];
+            for (int i = 0; i < nums.length; i++) {
+                if (i - k < 0) {
+                    ans[i] = -1;
+                } else if (i + k >= nums.length) {
+                    ans[i] = -1;
+                } else {
+                    if (i - k == 0) {
+                        ans[i] = (int) (preSums[i + k] / (2 * k + 1));
+                    } else {
+                        ans[i] = (int) ((preSums[i + k] - preSums[i - k - 1]) / (2 * k + 1));
+                    }
+                }
+            }
+            return ans;
+        }
+    }
+}
