push

src/main/java/com/jutem/cases/java8/lambda/ToListCollector.java

@@ -0,0 +1,42 @@
+package com.jutem.cases.java8.lambda;
+
+import java.util.Set;
+import java.util.function.BiConsumer;
+import java.util.function.BinaryOperator;
+import java.util.function.Function;
+import java.util.function.Supplier;
+import java.util.stream.Collector;
+
+/**
+ * @author [email protected]
+ * @create 2019-09-28
+ */
+public class ToListCollector implements Collector{
+    /**
+     * @return
+     */
+    @Override
+    public Supplier supplier() {
+        return null;
+    }
+
+    @Override
+    public BiConsumer accumulator() {
+        return null;
+    }
+
+    @Override
+    public BinaryOperator combiner() {
+        return null;
+    }
+
+    @Override
+    public Function finisher() {
+        return Function.identity();
+    }
+
+    @Override
+    public Set<Characteristics> characteristics() {
+        return null;
+    }
+}

src/main/java/com/jutem/cases/leetcode/DeleteNodeInALinkedList.java

@@ -0,0 +1,31 @@
+package com.jutem.cases.leetcode;
+
+/**
+ * @author [email protected]
+ * @create 2020-09-13
+ */
+public class DeleteNodeInALinkedList {
+    /**
+     * Definition for singly-linked list.
+     * public class ListNode {
+     * int val;
+     * ListNode next;
+     * ListNode(int x) { val = x; }
+     * }
+     */
+    public void deleteNode(ListNode node) {
+        node.val = node.next.val;
+        node.next = node.next.next;
+    }
+
+    public class ListNode {
+        int val;
+        ListNode next;
+
+        ListNode(int x) {
+            val = x;
+        }
+    }
+
+
+}

src/main/java/com/jutem/cases/leetcode/TwoSum.java

@@ -0,0 +1,66 @@
+package com.jutem.cases.leetcode;
+
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
+
+public class TwoSum {
+    public static void main(String[] args) {
+        twoSum(new int[]{3,2,4}, 6);
+    }
+
+    public static int[] twoSum(int[] nums, int target) {
+        Map<Integer, Integer> map = new HashMap<>();
+        for (int i = 0; i < nums.length; i++) {
+            Integer index = map.get(nums[i]);
+            if(index == null || i > index) {
+                map.put(nums[i], i);
+            }
+        }
+
+        for (int i = 0; i < nums.length; i++) {
+            int least = target - nums[i];
+            Integer index = map.get(least);
+            if(index != null && i != index) {
+                return new int[]{i, index};
+            }
+        }
+        return null;
+    }
+
+    private int[] firstSolution(int[] nums, int target) {
+        int[] cal = Arrays.copyOf(nums, nums.length);
+        Arrays.sort(cal);
+        for(int head = 0, tail = nums.length - 1; head != tail;) {
+            int sum = cal[head] + cal[tail];
+            if(sum == target) {
+                return new int[]{indexFirst(nums, cal[head]), indexLast(nums, cal[tail])};
+            }
+            if(sum > target) {
+                tail --;
+            } else {
+                head ++;
+            }
+        }
+        return null;
+    }
+
+    private int indexLast(int[] nums, int num) {
+        for(int i = nums.length - 1; i >= 0; i --) {
+            if(nums[i] == num) {
+                return i;
+            }
+        }
+        return 0;
+    }
+
+    private int indexFirst(int[] nums, int num) {
+        for(int i = 0; i < nums.length; i ++) {
+            if(nums[i] == num) {
+                return i;
+            }
+        }
+        return 0;
+    }
+
+}

src/main/java/com/jutem/cases/spring/bootstrap/MyBeanPostProcess.java

@@ -4,6 +4,9 @@
 import org.springframework.beans.factory.config.BeanPostProcessor;
 import org.springframework.stereotype.Component;
 
+import java.util.HashMap;
+import java.util.Map;
+
 @Component
 public class MyBeanPostProcess implements BeanPostProcessor{
 
@@ -16,4 +19,5 @@ public Object postProcessBeforeInitialization(Object bean, String beanName) thro
     public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
         return bean;
     }
+
 }