add some solution

Author: coderbean

src/main/java/leetcode/_146_/LRUCache2.java

@@ -0,0 +1,31 @@
+package leetcode._146_;
+
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+/**
+ * Created by zhangbo54 on 2019-07-23.
+ */
+class LRUCache2<K, V> extends LinkedHashMap<K, V> {
+
+    private int maxSize;
+
+    public LRUCache2(int maxSize) {
+        // 第三个参数表示是否按照访问顺序组织链表
+        super(maxSize, 0.75f, true);
+        this.maxSize = maxSize;
+    }
+
+    @Override
+    protected boolean removeEldestEntry(Map.Entry<K, V> eldest) {
+        return this.size() > maxSize;
+    }
+}
+
+/**
+ * Your LRUCache object will be instantiated and called as such:
+ * LRUCache obj = new LRUCache(capacity);
+ * int param_1 = obj.get(key);
+ * obj.put(key,value);
+ */

src/main/java/leetcode/_70_/Main.java

@@ -6,11 +6,19 @@
 public class Main {
     public static void main(String[] args) {
         Solution solution = new Solution();
-        System.out.println( solution.climbStairs(0));
-        System.out.println( solution.climbStairs(2));
-        System.out.println( solution.climbStairs(3));
-        System.out.println( solution.climbStairs(1));
-        System.out.println( solution.climbStairs(111));
+        long l = System.currentTimeMillis();
+        // System.out.println( solution.climbStairs(1));
+        System.out.println(solution.climbStairs(2));
+        System.out.println(solution.climbStairs(3));
+        System.out.println(solution.climbStairs(1));
+        System.out.println("-----------------");
+        System.out.println(solution.climbStairs(40));
+        System.out.println(System.currentTimeMillis() - l);
     }
 }
 
+// 1
+//         2
+//         3
+//         1
+//         165580141

src/main/java/leetcode/_70_/Solution.java

@@ -4,7 +4,6 @@ class Solution {
     public int climbStairs(int n) {
         int[] dp = new int[n + 1];
         return this.climbStairs(dp, n);
-
     }
 
     private int climbStairs(int[] dp, int n) {

src/main/java/leetcode/_70_/Solution1.java

@@ -0,0 +1,13 @@
+package leetcode._70_;
+
+/**
+ * Created by jacob on 2019-08-20.
+ */
+public class Solution1 {
+    public int climbStairs(int n) {
+        if (n <= 2) {
+            return n;
+        }
+        return climbStairs(n - 1) + climbStairs(n - 2);
+    }
+}

src/main/java/leetcode/_70_/Solution2.java

@@ -0,0 +1,18 @@
+package leetcode._70_;
+
+/**
+ * Created by jacob on 2019-08-20.
+ */
+public class Solution2 {
+    public int climbStairs(int n) {
+        int[] dp = new int[n + 1];
+        for (int i = 1; i <= n; i++) {
+            if (i <= 2) {
+                dp[i] = i;
+            } else {
+                dp[i] = dp[i - 1] + dp[i - 2];
+            }
+        }
+        return dp[n];
+    }
+}