add 1029

fishercoder1534 · fishercoder1534 · commit ba80cda80ffa · 2019-05-26T09:11:09.000-07:00
diff --git a/README.md b/README.md
@@ -32,6 +32,7 @@ Your ideas/fixes/algorithms are more than welcome!
 |1037|[Valid Boomerang](https://leetcode.com/problems/valid-boomerang/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1037.java) | O(1) | O(1) | |Easy|Math|
 |1033|[Moving Stones Until Consecutive](https://leetcode.com/problems/moving-stones-until-consecutive/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1033.java) | O(1) | O(1) | |Easy|Math|
 |1030|[Matrix Cells in Distance Order](https://leetcode.com/problems/matrix-cells-in-distance-order/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1030.java) | O(R*C) | O(1) | |Easy|
+|1029|[Two City Scheduling](https://leetcode.com/problems/two-city-scheduling/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1029.java) | O(nlogn) | O(1) | |Easy|
 |1022|[Sum of Root To Leaf Binary Numbers](https://leetcode.com/problems/sum-of-root-to-leaf-binary-numbers/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1022.java) | O(n) | O(n) | |Easy|
 |1021|[Remove Outermost Parentheses](https://leetcode.com/problems/remove-outermost-parentheses/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1021.java) | O(n) | O(n) | |Easy|
 |1020|[Number of Enclaves](https://leetcode.com/problems/number-of-enclaves/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1020.java) | O(mn) | O(mn) | |Medium|Graph, DFS, BFS, recursion|
diff --git a/src/main/java/com/fishercoder/solutions/_1029.java b/src/main/java/com/fishercoder/solutions/_1029.java
@@ -0,0 +1,48 @@
+package com.fishercoder.solutions;
+
+import java.util.Arrays;
+
+/**
+ * 1029. Two City Scheduling
+ *
+ * There are 2N people a company is planning to interview.
+ * The cost of flying the i-th person to city A is costs[i][0], and the cost of flying the i-th person to city B is costs[i][1].
+ * Return the minimum cost to fly every person to a city such that exactly N people arrive in each city.
+ *
+ * Example 1:
+ *
+ * Input: [[10,20],[30,200],[400,50],[30,20]]
+ * Output: 110
+ * Explanation:
+ * The first person goes to city A for a cost of 10.
+ * The second person goes to city A for a cost of 30.
+ * The third person goes to city B for a cost of 50.
+ * The fourth person goes to city B for a cost of 20.
+ *
+ * The total minimum cost is 10 + 30 + 50 + 20 = 110 to have half the people interviewing in each city.
+ *
+ * Note:
+ *
+ * 1 <= costs.length <= 100
+ * It is guaranteed that costs.length is even.
+ * 1 <= costs[i][0], costs[i][1] <= 1000
+ * */
+public class _1029 {
+    public static class Solution1 {
+        /**credit: https://leetcode.com/problems/two-city-scheduling/discuss/280173/Java-4-lines-intuitive-solution
+         * and
+         * https://leetcode.com/problems/two-city-scheduling/discuss/278771/Java-sort-solution*/
+        public int twoCitySchedCost(int[][] costs) {
+            Arrays.sort(costs, (a, b) -> (a[0] - a[1] - (b[0] - b[1])));
+            int cost = 0;
+            for (int i = 0; i < costs.length; i++) {
+                if (i < costs.length / 2) {
+                    cost += costs[i][0];
+                } else {
+                    cost += costs[i][1];
+                }
+            }
+            return cost;
+        }
+    }
+}
diff --git a/src/test/java/com/fishercoder/_1029Test.java b/src/test/java/com/fishercoder/_1029Test.java
@@ -0,0 +1,42 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._1029;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class _1029Test {
+    private static _1029.Solution1 solution1;
+    private static int[][] costs;
+
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _1029.Solution1();
+    }
+
+    @Test
+    public void test1() {
+        costs = new int[][]{
+                {10, 20},
+                {30, 200},
+                {400, 50},
+                {30, 20}
+        };
+        assertEquals(110, solution1.twoCitySchedCost(costs));
+    }
+
+    @Test
+    public void test2() {
+        costs = new int[][]{
+                {259, 770},
+                {448, 54},
+                {926, 667},
+                {184, 139},
+                {840, 118},
+                {577, 469}
+        };
+        assertEquals(1859, solution1.twoCitySchedCost(costs));
+    }
+
+}
