Question

java利用二维数组打印5行星号，成金字塔形，分别是1 3 5 7 9 个星号

Answer 1

public static void main(String[] args) {
String n = JOptionPane.showInputDialog("请输入一个数字：");// 直接输入行号
int l = Integer.parseInt(n);
int k = l;
for (int i = 1; i <= k; i++) {
for (int j = 1; j <= l; j++)
System.out.print(" ");
l--;
for (int j = 1; j <= i*2-1; j++) {
System.out.print("*");// 显示星星
}
System.out.println();
}
}

Answer 2

public static void main(String[] args) {
String n = JOptionPane.showInputDialog("请输入一个数字：");// 直接输入行号
int l = Integer.parseInt(n);
int k = l;
for (int i = 1; i <= k; i++) {
for (int j = 1; j <= l; j++)
System.out.print(" ");
l--;
for (int j = 1; j <= i*2-1; j++) {
System.out.print("*");// 显示星星
}
System.out.println();
}
}

Answer 3

public static void main(String[] args)
{
for(int i = 0;i < 5;i++)
{
for(int j = 5;j > i;j--)
{
System.out.print(" ");
}
for(int a = 1;a < i+2;a++)
{
System.out.print("*");
}
for(int a = 2;a < i+2;a++)
{
System.out.print("*");
}
System.out.println();
}

}