【每日日报】第二十天

1 第三章上机练习

1.1 冒泡排序：

 1 package Line;
 2 
 3 import java.util.Arrays; 
 4 
 5 public class MaoPao {
 6     public static void main(String[] args){
 7     int[] ary= { 1,5,6,9,8,2,3 } ;
 8     for(int i=0;i<ary.length-1;i++){
 9         for(int j=0;j<ary.length-i-1;j++){
10             if(ary[j]>ary[j+1]){
11                 int t=ary[j];ary[j]=ary[j+1];ary[j+1]=t;
12             }
13         }
14         
15     }
16     System.out.println(Arrays.toString(ary));
17     }
18 }

　　1.2 插入排序

 1 package Line;
 2 
 3 import java.util.Arrays;
 4 
 5 public class ChaRu {
 6     public static void main(String[] arys){
 7         int[] ary={1,5,6,9,8,2,3};
 8         int i,j,k;
 9         for(i=1;i<ary.length;i++){
10             k=ary[i];
11             for(j=i-1;j>=0&&k<ary[j];j--){
12                 ary[j+1]=ary[j];
13             }ary[j+1]=k;
14         }
15         System.out.println(Arrays.toString(ary));
16     }
17 
18 }

　　1.3 选择排序

 1 package Line;
 2 
 3 import java.util.Arrays;
 4 
 5 public class XuanZe {
 6     public static void main(String[] args){
 7         int[] ary = {1,5,6,9,8,2,3};
 8         for(int i=0;i<ary.length-1;i++){
 9             for(int j=i+1;j<ary.length;j++){
10                 if(ary[i]>ary[j]) {
11                     int t=ary[i];ary[i]=ary[j];ary[j]=t;
12                 }
13             }
14         }
15         System.out.println(Arrays.toString(ary));
16     }
17 
18 }

　　2 随机生成五位数并排序

 1 package Array;
 2 import java.util.Arrays;
 3 import java.util.Random;
 4 public class ScPx {
 5     public static void main(String args[]){
 6     Random ran = new Random();
 7     int[] a = new int [5];
 8     for(int i=0;i<5;i++){
 9         a[i] = ran.nextInt(10);
10     }
11     for(int i=0;i<4;i++){
12         for(int j=i+1;j<5;j++){
13             if(a[i]<a[j]){
14                 int r=a[i];
15                 a[i]=a[j];
16                 a[j]=r;
17             }
18         }
19     }
20     System.out.println(Arrays.toString(a)); 
21  }
22 }

　　3 判断最大值

1 import java.util.*;
2 public class ZuiDa {
3     public static void main(String args[]){
4         Scanner s=new Scanner(System.in);
5         int a=s.nextInt();
6         int b=s.nextInt();
7         System.out.print(a>b?a:b);
8     }
9 }

2 没遇到什么问题

3 明天继续看书