数组
声明数组int[] array = null; array放在栈里
创建数组 array = new int[10]; 在堆中开辟区域
数组里面是对象的例子:Man[] mans = {new Man();new Man()};
int[] a=new int[10];//一经创建便有了默认值0
for (int i : a) {//输入a.for
System.out.println(i);
}
int[]b=reverse(a);//此处不用再new
for (int i : b) {
System.out.println(i);
}
二维数组:int[][] array = {{1,2,3},{4,5,6},{7,8,9}};
int [][]a={{1,2,3},{4,5,6},{7,8,9}};
for (int i = 0; i < a.length; i++) {//注意length的用法
for (int j = 0; j < a[i].length; j++) {
System.out.println(a[i][j]);
}
}
//增强循环输出二位数组
for (int[] ints : a) {//输入a.for
for (int anInt : ints) {//输入ints.for
System.out.println(anInt);
}
}
System.out.println(Arrays.toString(a));//[67, 23, 54, 79, 1, 3, 75, 34]
Arrays.sort(a);
System.out.println(Arrays.toString(a));//[1, 3, 23, 34, 54, 67, 75, 79]
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