数组遍历
数组遍历:依次输出数组中的每一个元素
数组的属性:arr.length 数组的长度
数组的最大索引:arr.length - 1
int[] arr = {11, 22, 33, 44};
for(int i = 0; i < arr.length; i++){
System.out.println(arr[i]);
}
获取最值
int[] arr1 = new int[]{11, 33, -44, 22};
int max = arr1[0];
for(int i = 1; i<arr1.length; i++){
if(arr1[i] > max){
max = arr1[i];
}
}
System.out.println(max);
数组反转
写法1:
int[] arr = new int[100];
for(int i = 0; i < arr.length; i++){
arr[i] = i + 1;
}
int left = 0, right= arr.length - 1;
while(left <= right){
int temp = arr[left];
arr[left] = arr[right];
arr[right] = temp;
left++;
right--;
}
for(int data : arr){
System.out.print(data + " ");
}
写法2:
int[] arr = new int[100];
for(int i = 0; i < arr.length; i++){
arr[i] = i + 1;
}
for(int i = 0; i< arr.length / 2; i++){
int temp = arr[i];
arr[i] = arr[arr.length - i - 1];
arr[arr.length - i - 1] = temp;
}
for(int data : arr){
System.out.print(data + " ");
}
查表法
char[] arr = {' ', '一', '二', '三', '四', '五', '六', '日',}
Scanner in = new Scanner(System.in);
System.out.println("请输入您要查询的星期(1-7)");
int week = in.nextInt();
System.out.println("星期" + arr[week]);
根据值查索引
int arr[] = {11, 22, 33, 44};
int value = 22;
int index = -1;
for(int i = 0; i < arr.length; i++){
if(arr[i] == value){
index = i;
break;
}
}