class Solution {
    public void sortColors(int[] nums) {
        for(int i =0;i<nums.length-1;i++){
            for(int j=i+1;j<nums.length;j++){
                if(nums[i]>nums[j]){
                    int tmp=nums[i];
                    nums[i]=nums[j];
                    nums[j]=tmp;
                }
            }
        }
    }
}
Runtime: 1 ms, faster than 6.35% of Java online submissions for Sort Colors.

class Solution {
    public void sortColors(int[] nums) {
        int l = 0;
        int r = nums.length - 1;
        int index = 0;
        while(l <= r) {
            if(nums[l] == 0) {
                if(l > index) {
                    int tmp = nums[index];
                    nums[index] = nums[l];
                    nums[l] = tmp;
                    index++;
                }
                else {
                    l++;
                    index++;
                }
            }
            else if(nums[l] == 2) {
                int tmp = nums[r];
                nums[r] = 2;
                nums[l] = tmp;
                r--;
            }
            else l++;
        }
        
    }
}

import java.util.concurrent.BlockingQueue;
import java.util.concurrent.DelayQueue;
import java.util.concurrent.Delayed;
import java.util.concurrent.TimeUnit;
public class HandWritingQueue {
    public static void main(String[] args) {
        final BlockingQueue<DelayedElement> deque = new DelayQueue<>();
        Runnable producerRunnable = new Runnable() {
            int i = 10;
            public void run() {
                while (true && i>0) {
                    try {
                        --i;
                        System.out.println("producing "+i+",wait "+i+" seconds");
                        deque.put(new DelayedElement(1000 * i, "i=" + i));
                        Thread.sleep(200);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            }
        };
        Runnable customerRunnable = new Runnable() {
            public void run() {
                while (true) {
                    try {
                        System.out.println("consuming:" + deque.take().msg);
                        //Thread.sleep(500);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            }
        };

        Runnable getSize= new Runnable() {
            @Override
            public void run() {
                while (true) {
                    System.out.println("size="+deque.size());
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }

                }
            }
        };

        Thread thread1 = new Thread(producerRunnable);
        thread1.start();

        Thread thread2 = new Thread(customerRunnable);
        thread2.start();

        Thread thread3 = new Thread(getSize);
        thread3.start();

    }

        static class DelayedElement implements Delayed {

        private final long expire;
        private final String msg;

        public DelayedElement(long delay, String msg) {
            this.msg = msg;
            expire = System.currentTimeMillis() + delay;
        }

        @Override
        public long getDelay(TimeUnit unit) {
            return unit.convert(this.expire - System.currentTimeMillis(), TimeUnit.MILLISECONDS);
        }
        @Override
        public int compareTo(Delayed o) {
            return  -1;//FIFO
        }
    }
}

public int searchInsert(int[] nums, int target) {
    if (nums == null || nums.length == 0) {
        return 0;
    }
    if (target > nums[nums.length - 1]) {
        return nums.length;
    }
    int pos =1;
    for(int i =0;i<nums.length-1;i++){
         if(nums[i]<target && nums[i+1]>=target){
            pos = ++i;
            break;
        }
    }
    return  pos;
}

private int searchInsert(int[] nums, int target, int low, int high) {
        int mid = (low+high)/2;
        
        if (target < nums[mid]) {
            if (mid == 0 || target > nums[mid-1]) {
                return mid;
            }
            return searchInsert(nums, target, low, mid-1);
        }
        
        if (target > nums[mid]) {
            if (mid == nums.length-1 || target < nums[mid+1]) {
                return mid+1;
            }
            return searchInsert(nums, target, mid+1, high);
        }
        
        return mid;
    }

@SpringBootApplication
public class SpringTestApplication {
 
	public static void main(String[] args) {
		SpringApplication.run(SpringTestApplication.class, args);
	}

public static ConfigurableApplicationContext run(Object source, String... args) {
		return run(new Object[] { source }, args);
	}
 
public static ConfigurableApplicationContext run(Object[] sources, String[] args) {
		return new SpringApplication(sources).run(args);
	}
 
public SpringApplication(Object... sources) {
		initialize(sources);
	}

`private void initialize(Object[] sources) {
    // 在sources不为空时，保存配置类
    if (sources != null && sources.length > 0) {
        this.sources.addAll(Arrays.asList(sources));
    }
    // 判断是否为web应用
    this.webEnvironment = deduceWebEnvironment();
    // 获取并保存容器初始化类，通常在web应用容器初始化使用
    // 利用loadFactoryNames方法从路径MEAT-INF/spring.factories中找到所有的ApplicationContextInitializer
    setInitializers((Collection) getSpringFactoriesInstances(
        ApplicationContextInitializer.class));
    // 获取并保存监听器
    // 利用loadFactoryNames方法从路径MEAT-INF/spring.factories中找到所有的ApplicationListener
    setListeners((Collection) getSpringFactoriesInstances(ApplicationListener.class));
    // 从堆栈信息获取包含main方法的主配置类
    this.mainApplicationClass = deduceMainApplicationClass();
}

public ConfigurableApplicationContext run(String... args) {
    StopWatch stopWatch = new StopWatch();
    stopWatch.start();
    ConfigurableApplicationContext context = null;
    FailureAnalyzers analyzers = null;
    // 配置属性
    configureHeadlessProperty();
    // 获取监听器
    // 利用loadFactoryNames方法从路径MEAT-INF/spring.factories中找到所有的SpringApplicationRunListener
    SpringApplicationRunListeners listeners = getRunListeners(args);
    // 启动监听
    // 调用每个SpringApplicationRunListener的starting方法
    listeners.starting();
    try {
        // 将参数封装到ApplicationArguments对象中
        ApplicationArguments applicationArguments = new DefaultApplicationArguments(
            args);
        // 准备环境
        // 触发监听事件——调用每个SpringApplicationRunListener的environmentPrepared方法
        ConfigurableEnvironment environment = prepareEnvironment(listeners,
            applicationArguments);
        // 从环境中取出Banner并打印
        Banner printedBanner = printBanner(environment);
        // 依据是否为web环境创建web容器或者普通的IOC容器
        context = createApplicationContext();
        analyzers = new FailureAnalyzers(context);
        // 准备上下文
        // 1.将environment保存到容器中
        // 2.触发监听事件——调用每个SpringApplicationRunListeners的contextPrepared方法
        // 3.调用ConfigurableListableBeanFactory的registerSingleton方法向容器中注入applicationArguments与printedBanner
        // 4.触发监听事件——调用每个SpringApplicationRunListeners的contextLoaded方法
        prepareContext(context, environment, listeners, applicationArguments,
            printedBanner);
        // 刷新容器，完成组件的扫描，创建，加载等
        refreshContext(context);
        afterRefresh(context, applicationArguments);
        // 触发监听事件——调用每个SpringApplicationRunListener的finished方法
        listeners.finished(context, null);
        stopWatch.stop();
        if (this.logStartupInfo) {
            new StartupInfoLogger(this.mainApplicationClass)
                .logStarted(getApplicationLog(), stopWatch);
        }
        // 返回容器
        return context;
    }
    catch (Throwable ex) {
        handleRunFailure(context, listeners, analyzers, ex);
        throw new IllegalStateException(ex);
    }
}