Added p888 (#55)

teresachenec · fishercoder1534 · commit dc54494910ba · 2019-04-26T17:25:41.000-07:00
diff --git a/README.md b/README.md
@@ -69,6 +69,7 @@ Your ideas/fixes/algorithms are more than welcome!
 |897|[Increasing Order Search Tree](https://leetcode.com/problems/increasing-order-search-tree/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_897.java) | O(n) | O(n) | |Easy| DFS, recursion
 |896|[Monotonic Array](https://leetcode.com/problems/monotonic-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_896.java) | O(n) | O(1) | |Easy|
 |890|[Find and Replace Pattern](https://leetcode.com/problems/find-and-replace-pattern/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_890.java) | O(n) | O(1) | |Medium|
+|888|[Fair Candy Swap](https://leetcode.com/problems/fair-candy-swap/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_888.java) | O(n) | O(1) | |Easy|
 |884|[Uncommon Words from Two Sentences](https://leetcode.com/problems/uncommon-words-from-two-sentences/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_884.java) | O(n) | O(k) | |Easy|
 |876|[Middle of the Linked List](https://leetcode.com/problems/middle-of-the-linked-list/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_876.java) | O(n) | O(1) | |Easy|
 |872|[Leaf-Similar Trees](https://leetcode.com/problems/leaf-similar-trees/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_872.java) | O(n) | O(h) | |Easy| DFS, recursion
diff --git a/src/main/java/com/fishercoder/solutions/_888.java b/src/main/java/com/fishercoder/solutions/_888.java
@@ -0,0 +1,72 @@
+package com.fishercoder.solutions;
+
+import java.util.HashSet;
+
+/**
+ * 888. Fair Candy Swap
+ *
+ * Alice and Bob have candy bars of different sizes: A[i] is the size of the i-th bar of candy that Alice has, and B[j]
+ * is the size of the j-th bar of candy that Bob has.
+ *
+ * Since they are friends, they would like to exchange one candy bar each so that after the exchange, they both have the
+ * same total amount of candy.  (The total amount of candy a person has is the sum of the sizes of candy bars they have.)
+ *
+ * Return an integer array ans where ans[0] is the size of the candy bar that Alice must exchange, and ans[1] is the
+ * size of the candy bar that Bob must exchange.
+ *
+ * If there are multiple answers, you may return any one of them.  It is guaranteed an answer exists.
+ *
+ *
+ *
+ * Example 1:
+ *
+ * Input: A = [1,1], B = [2,2]
+ * Output: [1,2]
+ * Example 2:
+ *
+ * Input: A = [1,2], B = [2,3]
+ * Output: [1,2]
+ * Example 3:
+ *
+ * Input: A = [2], B = [1,3]
+ * Output: [2,3]
+ * Example 4:
+ *
+ * Input: A = [1,2,5], B = [2,4]
+ * Output: [5,4]
+ */
+
+public class _888 {
+    public static class Solution1 {
+        public int[] fairCandySwap(int[] A, int[] B) {
+            int aSum = 0;
+            int bSum = 0;
+            int diff = 0;
+            int [] ans = new int [2];
+            for(int bar : A)
+            {
+                aSum += bar;
+            }
+            for(int bar : B)
+            {
+                bSum += bar;
+            }
+            diff = aSum - bSum;
+            HashSet<Integer> set = new HashSet<>();
+            for(int bar : A)
+            {
+                set.add(bar);
+            }
+            for(int bar : B)
+            {
+                if(set.contains(bar + diff/2))
+                {
+                    ans[0] = bar + diff/2;
+                    ans[1] = bar;
+                    break;
+                }
+            }
+            return ans;
+        }
+    }
+}
diff --git a/src/test/java/com/fishercoder/_888Test.java b/src/test/java/com/fishercoder/_888Test.java
@@ -0,0 +1,48 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._888;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class _888Test {
+    private static _888.Solution1 solution1;
+
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _888.Solution1();
+    }
+
+    @Test
+    public void test1() {
+        int [] A = {1, 1};
+        int [] B = {2, 2};
+        int [] ans = {1, 2};
+        assertEquals(ans, solution1.fairCandySwap(A, B));
+    }
+
+    @Test
+    public void test2() {
+        int [] A = {1, 2};
+        int [] B = {2, 3};
+        int [] ans = {1, 2};
+        assertEquals(ans, solution1.fairCandySwap(A, B));
+    }
+
+    @Test
+    public void test3() {
+        int [] A = {2};
+        int [] B = {1, 3};
+        int [] ans = {2, 3};
+        assertEquals(ans, solution1.fairCandySwap(A, B));
+    }
+
+    @Test
+    public void test4() {
+        int [] A = {1, 2, 5};
+        int [] B = {2, 4};
+        int [] ans = {5, 4};
+        assertEquals(ans, solution1.fairCandySwap(A, B));
+    }
+}
