java中数组的使用-0511

class Demo02 
{
    public static void main(String[] args) 
    {
        /*int[] arr = new int[3];
        System.out.println(arr);
        System.out.println(arr.length);
        System.out.println(arr[0]);
        System.out.println(arr[1]);
        System.out.println(arr[2]);
        //给元素赋值
        arr[0] = 100;
        arr[1] = 200;
        arr[2] = 300;
        System.out.println(arr[0]);
        System.out.println(arr[1]);
        System.out.println(arr[2]);
        int[] arr2 = {11,12,13};
        int[] arr3 = new int[]{11,12,13};
        //数组遍历
        for(int i = 0;i<arr.length;i++){
           System.out.println(arr[i]);
        }*/
        //数组最大值
        int[] arr = {55,66,11,99,44,33,22};
        int max = arr[0];
        for(int i = 1;i<arr.length;i++){
               if(arr[i]>max){
                   max = arr[i];
               }
        }
             System.out.println(max);
    }
}

class Demo05
{
    public static void main(String[] args) 
    {
        /*int[][] arr = new int[2][4];
        //二维数组遍历
        for(int i = 0;i<arr.length;i++){
            for(int j = 0;j<arr[i].length;j++){
                System.out.println(arr[i][j]);
            }
        }
        //二维数组求和
        int sum = 0;
        for(int i = 0;i<arr.length;i++){
            for(int j = 0;j<arr[i].length;j++){
                sum+=arr[i][j];
            }
        }
        System.out.println(sum);*/
        //求总销售额和各个季度销售额
        /*int[][] arr = {{11,12},{21,22,23},{31,32,33,34}};
        int sum1 = 0;
        int sum = 0;
        for(int i = 0;i<arr.length;i++){
           for(int j = 0;j<arr[i].length;j++){
              sum +=arr[i][j];
              sum1 +=arr[i][j];
           }
            System.out.println(sum1);
            sum1 = 0;
        }
        System.out.println(sum);*/

    }
}