不同样式输出菱形

不同样式输出菱形

1、实心菱形

package mrzhangxd.xyz.demo;

/**
* CopyRight (C),2019
*
* @Package: mrzhangxd.xyz.demo
* @Name: Test
* @Auther: zhangxiaodong3
* @Creatte: 2019/12/19
* @Description: Output 7 lines of solid diamonds
*/

/*
Output style：
*
***
*****
***
*
Main idea：

1. Divide 7 rows of diamonds into 4 and 3 columns for output;

2.The first half
"" Quantity per line: 2 * i-1
Number of spaces per line: line-i
3. The lower part:
Number of spaces per line: i
"" Quantity per line: 2 * i-1
*/
public class Test {

public static void main(String[] args){

// The number of input lines is L, and the output diamond is (2L-1)
int L = 4;

// The first half of the output (4 lines)
for(int i = 1; i <= L; i++){

// Output the space of each line in the top half
for(int j = 1;j <= (L - i); j++){

System.out.print(" ");

}

// Output the "" sign of each line in the lower half
for(int j = 1; j <= (2i)-1; j++){

System.out.print("*");

}

System.out.println();
}

// The lower part of the output (3 lines)
for(int i = 1; i <= (L-1);i++){

// Output spaces for each line in the lower half
for(int j = 1;j <= i;j++){

System.out.print(" ");
}

// Output "" sign for each line in the lower half
for(int j = 1; j <= (2(L-i)-1);j++){

System.out.print("*");
}

System.out.println();
}

}

}

2、空心菱形

package mrzhangxd.xyz.demo;

/**
* CopyRight (C),2019
*
* @PackageName: mrzhangxd.xyz.demo
* @ClassName: Test2
* @Auther: zhangxiaodong3
* @Created: 2019/12/1915:51
* @Description: Output 7 rows of hollow diamonds...
/
/
Output style：
*
* *
* *
* *
*

Main idea：

1. Divide 7 rows of diamonds into 4 and 3 columns for output;

2.The first half
"" Quantity per line: 2 * i-1
Number of spaces per line: line-i
3. The lower part:
Number of spaces per line: i
"" Quantity per line: 2 * i-1
4. Consider where to output spaces and where to output ""
Set the line number to "n", then the position of the output "" is:
(j == 1 | j == ((2 * n) -1))

*/
public class Test2 {

public static void main(String[] args){

// The number of input lines is L, and the output diamond is (2L-1)
int L = 4;

// Determine the number of rows in the upper half of the output diamond
for(int i = 1;i <= L; i ++){

// Output the number of spaces per line
for(int j = 1;j <= (L-i);j++){

System.out.print(" ");
}

// Output the number of "" in each line
for(int j = 1;j <= ((2i)-1);j++){

// Output "" in the if condition, otherwise output spaces
if(j == 1 || j == ((2i)-1)){

System.out.print("*");

}else{

System.out.print(" ");

}
}

System.out.println();

}

// Determine the number of rows of the output diamond in the lower half
for(int i = 1;i <= (L-1);i++){

// Output the number of spaces per line
for(int j = 1;j <= i;j++){

System.out.print(" ");

}

// Output the number of "" in each line
for(int j = 1;j <= (2(L-i)-1);j++){

// Output "" in the if condition, otherwise output spaces
if(j == 1 || j == 2(L-i)-1){

System.out.print("*");

}else{

System.out.print(" ");
}

}

System.out.println();
}

}

}

PS：上代码就可以了，思路代码注解里有...