编写一个 Java 程序,使用 for 循环打印三角形数字模式。
package Shapes3;
import java.util.Scanner;
public class TriangleNum1 {
private static Scanner sc;
public static void main(String[] args) {
sc = new Scanner(System.in);
System.out.print("Enter Triangle Number Pattern Rows = ");
int rows = sc.nextInt();
System.out.println("Printing Triangle Number Pattern");
for (int i = 1; i <= rows; i++ )
{
for (int j = rows; j > i; j-- )
{
System.out.print(" ");
}
for(int k = 1; k <= i; k++)
{
System.out.print(k + " ");
}
System.out.println();
}
}
}

此程序使用 while 循环打印数字三角形模式。
package Shapes3;
import java.util.Scanner;
public class TriangleNum2 {
private static Scanner sc;
public static void main(String[] args) {
sc = new Scanner(System.in);
System.out.print("Enter Triangle Number Pattern Rows = ");
int rows = sc.nextInt();
System.out.println("Printing Triangle Number Pattern");
int j, k, i = 1;
while( i <= rows )
{
j = rows;
while(j > i )
{
System.out.print(" ");
j--;
}
k = 1;
while(k <= i)
{
System.out.print(k + " ");
k++;
}
System.out.println();
i++;
}
}
}
Enter Triangle Number Pattern Rows = 8
Printing Triangle Number Pattern
1
1 2
1 2 3
1 2 3 4
1 2 3 4 5
1 2 3 4 5 6
1 2 3 4 5 6 7
1 2 3 4 5 6 7 8
这个 示例 使用 do while 循环显示数字三角形模式。
package Shapes3;
import java.util.Scanner;
public class TriangleNum3 {
private static Scanner sc;
public static void main(String[] args) {
sc = new Scanner(System.in);
System.out.print("Enter Rows = ");
int rows = sc.nextInt();
System.out.println("");
int j, k, i = 1;
do
{
j = rows;
do
{
System.out.print(" ");
} while(j-- > i );
k = 1;
do
{
System.out.print(k + " ");
} while(++k <= i);
System.out.println();
} while(++i <= rows );
}
}
Enter Rows = 9
1
1 2
1 2 3
1 2 3 4
1 2 3 4 5
1 2 3 4 5 6
1 2 3 4 5 6 7
1 2 3 4 5 6 7 8
1 2 3 4 5 6 7 8 9