Add house-robber

Author: lewis617

ArrayList/ArrayList.js

@@ -162,6 +162,29 @@ function ArrayList() {
     findNSum(array, M, N, [], results);
     return results;
   };
+
+  var rob = function (array) {
+    var last = 0,
+      now = 0;
+    for (var i = 0; i < array.length; i++) {
+      var temp = last;
+      last = now;
+      now = Math.max(temp + array[i], now);
+    }
+
+    return now;
+  };
+
+  this.simpleRob = function () {
+    return rob(array);
+  };
+
+  this.circleRob = function () {
+    if (array.length === 1) {
+      return array[0];
+    }
+    return Math.max(rob(array.slice(1)), rob(array.slice(0, array.length - 1)));
+  }
 }
 
 module.exports = ArrayList;

ArrayList/ArrayList.test.js

@@ -45,4 +45,18 @@ test('ArrayList', function () {
   expect(array.NSum(2, 6)).toEqual([[1, 5], [2, 4]]);
   expect(array.NSum(3, 7)).toEqual([[1, 2, 4]]);
   expect(array.NSum(4, 14)).toEqual([[2, 3, 4, 5]]);
+
+  function createRobArray() {
+    var array = new ArrayList();
+    array.insert(2);
+    array.insert(0);
+    array.insert(0);
+    array.insert(4);
+    array.insert(5);
+    return array;
+  }
+
+  array = createRobArray();
+  expect(array.simpleRob()).toBe(7);
+  expect(array.circleRob()).toBe(6);
 });

README.md

@@ -38,6 +38,8 @@
 
 [数组搜索算法题：求和为定值的多个数](https://lewis617.github.io/2017/03/09/n-sum/)
 
+[动态规划算法题：打家劫舍](https://lewis617.github.io/2017/03/10/house-robber/)
+
 ## 其他教程
 
 [React+Redux系列教程](https://github.com/lewis617/react-redux-tutorial)