Java小练习

Posted 2022-09-23 datacenter

1、输出乘法表

 1 public class Test 
 2     public static void main(String[] args) 
 3 
 4         int a, b, c;
 5         for (a = 1; a < 10; a++) 
 6             for (b = 1; b <= a; b++) 
 7                 c = a * b;
 8                 System.out.print(a + "*" + b + "=" + c);
 9                 System.out.print(" ");
10             
11             System.out.println();
12         
13 

2、打印水仙花数（水仙花数是指一个 3 位数，它的每个位上的数字的 3次幂之和等于它本身）

 1 public class Test 
 2     public static void main(String[] args) 
 3 
 4         int e, d, f, g;
 5         for (e = 100; e < 1000; e++) 
 6             d = e / 100;
 7             f = e / 10 % 10;
 8             g = e % 10;
 9             if (e == d * d * d + f * f * f + g * g * g)
10                 System.out.println(e);
11         
12 

3、找出所有4位数的9倍是该数的反序数，例如1089的4倍是9801

 1 public class Test 
 2     public static void main(String[] args) 
 3         int h, j, k, l, m;
 4         for (m = 1000; m < 10000; m++) 
 5             h = m / 1000;
 6             j = m / 100 % 10;
 7             k = m / 10 % 100;
 8             l = m % 10;
 9             if (m * 9 == l * 1000 + k * 100 + j * 10 + h)
10                 System.out.println(m);
11         
12 

4、打印一个菱形

 1 public class ZHOU 
 2     public static void main(String[] args) 
 3         int ab,abc,f,g;
 4         for(ab=1;ab<5;ab++)
 5             for(f=4;f>ab;f--)
 6                 System.out.print(" ");
 7             
 8             for (abc=1;abc<2*ab;abc++)
 9                 System.out.print("*");
10             
11             for(g=4;g>ab;g--)
12                 System.out.print(" ");
13             
14             System.out.println(" ");
15         
16