java打印三角形

/**
 * 实心三角形
      *
     ***
    *****
   *******
  *********
 ***********
空心三角形
      *
     * *
    *   *
   *     *
  *       *
 ***********
 */

import java.util.Scanner;

public class TestWork {
public static void main(String[] args) {
System.out.println("请输入行数");
Scann
4000
er sc = new Scanner(System.in);
if (sc.hasNextInt()) {
int rownum = sc.nextInt();
if (rownum > 1) {
System.out.println("实心三角形");
for (int i = 1; i <= rownum; i++) {
/*
* for(int k=0;k<=rownum-i;k++) { System.out.print(" "); }
*/
for (int k = i; k <= rownum; k++) {
System.out.print(" ");
}
for (int j = 1; j <= 2 * i - 1; j++) {
System.out.print("*");
}
System.out.println();
}
System.out.println("空心三角形");
for (int i = 1; i <= rownum; i++) {
for (int k = i; k <= rownum; k++) {
System.out.print(" ");
}
for (int j = 1; j <= 2 * i - 1; j++) {
if (i == 1 || i == rownum) {
System.out.print("*");
} else {
if (j == 1 || j == 2 * i - 1) {
System.out.print("*");
} else {
System.out.print(" ");
}
}
}
System.out.println();
}
} else {
System.out.println("请输入大于1的正整数");
}
} else {
System.out.println("请输入大于1的正整数");
}
}
}