实现数组的冒泡排序,二分查找,顺序查找,最大值,最小值,数组逆序,数组数字排列等
import java.util.Arrays;
public class test {
public static void main(String[] args) {
int[] arr = {1,2,3,4,5,6,7,8,9};
int[] newArr = Arrays.copyOf(arr, arr.length);
max(newArr,arr.length);//最大值
min(newArr,arr.length);//最小值
ave(newArr,arr.length);//平均值
fan(newArr,arr.length);//逆置
bubbleSort(newArr,arr.length);//冒泡排序
System.out.println("二分查找:" + binarySearch(newArr,5,arr.length));//二分查找
}
//最大值查找
public static void max(int[] array,int se) {
int tem = array[0];
for (int i = 0; i <se ; i++) {
if(array[i] > tem) {
tem = array[i];
}
}
System.out.println("max:" + tem);
}
//最小2值查找
public static void min(int[] array,int se) {
int tem = array[0];
for (int i = 0; i <se ; i++) {
if(array[i] < tem) {
tem = array[i];
}
}
System.out.println("min:" + tem);
}
//计算平均值
public static void ave(int[] array,int se) {
double tem = 0.0;
for (int i = 0; i <se ; i++) {
tem += array[i];
} tem = tem / (double)se;
System.out.println("ave:" + tem);
}
//数组逆置
public static void fan(int[] array,int se) {
int[] ret = new int[se];
for (int i = 0; i <se ; i++) {
ret[i] = array[se - 1 - i];
}
System.out.println("逆置:" + Arrays.toString(ret));
}
//实现数组的冒泡排序
public static void bubbleSort(int[] array,int se) {
int[] ret = Arrays.copyOf(array, se);
for (int i = 0; i < se ; i++) {
boolean flat = true;
for (int j = 0; j < se - i - 1; j++) {
if(ret[j] > ret[j+1]) {
int max = ret[j];
ret[j] = ret[j+1];
ret[j+1] = max;
flat = false;
}
}if (flat){
break;
}
}System.out.println("冒泡排序" + Arrays.toString(ret));
}
//实现数组的二分查找
public static int binarySearch(int[] array,int key,int right) {
int left = 0;
if(left > right) {
return -1;
}
int mid = (left+right) >>> 1;
if(array[mid] == key) {
return mid;
}else if (array[mid] < key) {
return binarySearch(array,key,left = mid+1);
}else {
return binarySearch(array,key,right = mid-1);
}
}