排序算法及先进先出等简单程序

1. 快速/冒泡排序

public class OrderTest {

	public static void main(String[] args) {
		int[] array = {2,1,343,2,43,431,7,49};
		// 冒泡排序
		//bubbleSort(array);
		//快速排序
		quickSort(array,0,7);
	}
	
	public static void bubbleSort(int[] array) {
		
		int temp;
		for(int i=0; i< array.length; i++) {
			for(int j=0;jarray[j+1]) {
					temp = array[j];
					array[j]=array[j+1];
					array[j+1]= temp;
				}
			}
		}
		System.out.println(Arrays.toString(array));
	}

	public static void quickSort(int[] array,int low,int high) {
		int i,j,temp,t;
		if (low > high) {
			return;
		}
		i = low;
		j = high;
		temp = array[i];
		while(i < j) {
			while(array[j] >= temp && j > i) {
				j--;
			}
			
			while(array[i] <= temp && j > i) {
				i++;
			}
			
			if (j>i) {
				t = array[j];
				array[j] = array[i];
				array[i] = t;
			}
		}
		
		array[low] = array[i];
		array[i] = temp;
		System.out.println(temp + Arrays.toString(array));
		quickSort(array, low, j-1);
		quickSort(array, i+1, high);
	}
}

2. 杨辉三角

public class Triangle {
	
	private static Scanner sc;
	private static int n;
	private static int[][] triangleArray;
	
	public static void main(String[] args) {

		sc = new Scanner(System.in);
		n = sc.nextInt();
		triangleArray = new int[n][n];
		
		for(int i=0; i 0; j--) {
				System.out.print("  ");
			}
			// 每个数占3格，且每个数之间空1格
			for(j = 0; j < i; j++) {
				System.out.printf("%3d ", triangleArray[i][j]);
			}
			// 最后1个数，换行
			System.out.printf("%3d\n", triangleArray[i][j]);
		}		
	}

}

3.先进先出队列

public class Queue {
	
	  private int maxSize;
	  private Object[] queueArray;
	  private int front;
	  private int rear;
	  private int size;
	  
	  public Queue(int length) {
		  maxSize = length;
		  queueArray = new Object[maxSize];
		  front = 0;
		  rear = -1;
		  size = 0;
	  }
	  
	  public boolean isFull(){
		return (rear + 2 == front || front + maxSize -2 == rear);
	  }
	  public boolean isEmpty(){
		return (rear + 1 == front || front + maxSize -1 == rear);  
	  }
	  
	  public String enQueue(String str) {
		if (isFull()) {
			throw new RuntimeException("队列已满，" + str + " 不能入队！");
		}
		queueArray[++rear] = str;
		size++;
		
		return str;
	  }
	  
	  public String deQueue() {
		  if (isEmpty()) {
			  throw new RuntimeException("队列为空，" +  " 不能出队！");
			}
		  String str = (String) queueArray[front++];
		  size--;
		  
		return str;
	  }
	  
	  public int queueSize() {
		  return size;
	  }
	public static void main(String[] args) {
		Queue queue = new Queue(5);
		queue.enQueue("a");
		queue.enQueue("b");
		queue.enQueue("c");
		queue.enQueue("d");
		//queue.enQueue("e");
		
		System.out.println("队列是否为空： " + queue.isEmpty() + "  队列是否满： " + queue.isFull());
		System.out.println("队列大小：" + queue.queueSize());
		
		int size = queue.queueSize();
		for(int i = 0; i < size; i++){
			String str = queue.deQueue();
			System.out.print(str + " ");
		}

		
	}

}