add 985

fishercoder1534 · fishercoder1534 · commit 86d1d478880e · 2019-02-03T08:48:47.000-08:00
diff --git a/README.md b/README.md
@@ -29,6 +29,7 @@ Your ideas/fixes/algorithms are more than welcome!
 
 |  #  |      Title     |   Solutions   | Time          | Space         | Video  | Difficulty  | Tag                   
 |-----|----------------|---------------|---------------|---------------|--------|-------------|-------------
+|985|[Sum of Even Numbers After Queries](https://leetcode.com/problems/sum-of-even-numbers-after-queries/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_985.java) | O(n) | O(n) | |Easy| Array
 |977|[Squares of a Sorted Array](https://leetcode.com/problems/squares-of-a-sorted-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_977.java) | O(nlogn) | O(1) | |Easy| Array
 |976|[Largest Perimeter Triangle](https://leetcode.com/problems/largest-perimeter-triangle/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_976.java) | O(nlogn) | O(1) | |Easy| Math Array 
 |974|[Subarray Sums Divisible by K](https://leetcode.com/problems/subarray-sums-divisible-by-k/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_974.java) | O(n) | O(n) | |Medium| Array|
diff --git a/src/main/java/com/fishercoder/solutions/_985.java b/src/main/java/com/fishercoder/solutions/_985.java
@@ -0,0 +1,52 @@
+package com.fishercoder.solutions;
+
+/**
+ * 985. Sum of Even Numbers After Queries
+ *
+ * We have an array A of integers, and an array queries of queries.
+ * For the i-th query val = queries[i][0], index = queries[i][1], we add val to A[index].  Then, the answer to the i-th query is the sum of the even values of A.
+ * (Here, the given index = queries[i][1] is a 0-based index, and each query permanently modifies the array A.)
+ * Return the answer to all queries.  Your answer array should have answer[i] as the answer to the i-th query.
+ *
+ * Example 1:
+ *
+ * Input: A = [1,2,3,4], queries = [[1,0],[-3,1],[-4,0],[2,3]]
+ * Output: [8,6,2,4]
+ * Explanation:
+ * At the beginning, the array is [1,2,3,4].
+ * After adding 1 to A[0], the array is [2,2,3,4], and the sum of even values is 2 + 2 + 4 = 8.
+ * After adding -3 to A[1], the array is [2,-1,3,4], and the sum of even values is 2 + 4 = 6.
+ * After adding -4 to A[0], the array is [-2,-1,3,4], and the sum of even values is -2 + 4 = 2.
+ * After adding 2 to A[3], the array is [-2,-1,3,6], and the sum of even values is -2 + 6 = 4.
+ *
+ * Note:
+ *
+ * 1 <= A.length <= 10000
+ * -10000 <= A[i] <= 10000
+ * 1 <= queries.length <= 10000
+ * -10000 <= queries[i][0] <= 10000
+ * 0 <= queries[i][1] < A.length
+ */
+public class _985 {
+  public static class Solution1 {
+    public int[] sumEvenAfterQueries(int[] A, int[][] queries) {
+      int[] result = new int[A.length];
+      for (int i = 0; i < A.length; i++) {
+        int col = queries[i][1];
+        A[col] = A[col] + queries[i][0];
+        result[i] = computeEvenSum(A);
+      }
+      return result;
+    }
+
+    private int computeEvenSum(int[] A) {
+      int sum = 0;
+      for (int num : A) {
+        if (num % 2 == 0) {
+          sum += num;
+        }
+      }
+      return sum;
+    }
+  }
+}
diff --git a/src/test/java/com/fishercoder/_985Test.java b/src/test/java/com/fishercoder/_985Test.java
@@ -0,0 +1,29 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._985;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertArrayEquals;
+
+public class _985Test {
+  private static _985.Solution1 solution1;
+  private static int[] expected;
+  private static int[] actual;
+  private static int[] A;
+  private static int[][] queries;
+
+  @BeforeClass
+  public static void setup() {
+    solution1 = new _985.Solution1();
+  }
+
+  @Test
+  public void test1() {
+    A = new int[] {1, 2, 3, 4};
+    queries = new int[][] {{1, 0}, {-3, 1}, {-4, 0}, {2, 3}};
+    expected = new int[] {8, 6, 2, 4};
+    actual = solution1.sumEvenAfterQueries(A, queries);
+    assertArrayEquals(expected, actual);
+  }
+}
