From 6931dd4d7bcc2725f2d911ba865ce9c3a69c485c Mon Sep 17 00:00:00 2001
From: Xusong Yuan <longlong354@hotmail.com>
Date: Sat, 11 May 2019 15:48:55 +0800
Subject: [PATCH] submit week 04 assignment

---
 Week_04/id_44/LeetCode_169_044.java | 20 ++++++++++++++++++++
 Week_04/id_44/LeetCode_746_044.java | 20 ++++++++++++++++++++
 2 files changed, 40 insertions(+)
 create mode 100644 Week_04/id_44/LeetCode_169_044.java
 create mode 100644 Week_04/id_44/LeetCode_746_044.java

diff --git a/Week_04/id_44/LeetCode_169_044.java b/Week_04/id_44/LeetCode_169_044.java
new file mode 100644
index 00000000..acbff58d
--- /dev/null
+++ b/Week_04/id_44/LeetCode_169_044.java
@@ -0,0 +1,20 @@
+public class LeetCode_169_044 {
+    public int majorityElement(int[] nums) {
+        return divc(nums, 0, nums.length - 1); 
+    }
+    private int divc(int[] nums, int l, int r){
+        if(l == r)
+            return nums[l];
+        int mid = l + (r - l)/2;
+        int ls = divc(nums, l, mid);
+        int rs = divc(nums, mid+1, r);
+        if(ls == rs)
+            return ls;
+        int c1 = 0, c2 = 0;
+        for(int i = l; i <= r; i++){
+            if(nums[i] == ls) c1++;
+            if(nums[i] == rs) c2++;
+        }
+        return c1 > c2 ? ls : rs;
+    }
+}
diff --git a/Week_04/id_44/LeetCode_746_044.java b/Week_04/id_44/LeetCode_746_044.java
new file mode 100644
index 00000000..c8834f49
--- /dev/null
+++ b/Week_04/id_44/LeetCode_746_044.java
@@ -0,0 +1,20 @@
+class LeetCode_746_044 {
+    public int minCostClimbingStairs(int[] cost) {
+        int step[] = new int[1024];
+        step[0] = 0;
+        step[1] = 0;
+        if (cost.length == 0) {
+            return 0;
+        }
+        if (cost.length == 1) {
+            return cost[0];
+        }
+        if (cost.length == 2) {
+            return Math.min(cost[0], cost[1]);
+        }
+        for (int i = 2; i <= cost.length; i++) {
+            step[i] = Math.min(step[i - 1] + cost[i - 1], step[i - 2] + cost[i - 2]);
+        }
+        return step[cost.length];
+    }
+}