数组的定义:
int[] arr = new int[5];int[] arr1 = {1,2,3,4,5};long[] arr2 = new long[6];String[] strs = new String[5];Person[] ps = new Person[5];
数组的操作:
int[] arr = {45, 34, 53, 43};Arrays.sort(arr);System.out.println(Arrays.toString(arr));// 二分搜索法(使用之前需要先排序)int i = Arrays.binarySearch(arr, 34);System.out.println(i);int[] newArr = Arrays.copyOf(arr, 7);int[] newArr1 = Arrays.copyOfRange(arr, 1, 3);System.out.println(Arrays.toString(newArr));System.out.println(Arrays.toString(newArr1));int j = Arrays.binarySearch(arr, 1, 3, 34);System.out.println(j);
冒泡排序:
int[] arr = {23,12,48,56,45};
int temp = -1;for(int i=0;i) {for(int j=i+1;j ) {if(arr[i]>arr[j]) {temp = arr[i];arr[i] = arr[j];arr[j] = temp;}}}System.out.println(Arrays.toString(arr));
直接选择排序:
int[] arr = {23,12,48,56,45};
for(int i=0;i) {int tem = i;for(int j=i;j ) {if(arr[j] < arr[tem]) {tem = j;}}int temp1 = arr[i];arr[i] = arr[tem];arr[tem] = temp1;}System.out.println(Arrays.toString(arr));
反转排序:
int[] arr = {23,12,48,56,45};
for(int i=0;i) {int temp = arr[i];arr[i] = arr[arr.length-i-1];arr[arr.length-i-1] = temp;}System.out.println(Arrays.toString(arr))