Java –如何打印金字塔

一时失言乱红尘 2023-02-15 05:09 24阅读 0赞

一个Java示例，用于打印半金字塔和全金字塔。

CreatePyramid.java

package com.mkyong;
    
    import java.util.Collections;
    
    public class CreatePyramid {
    
        public static void main(String[] args) {
    
            int rows = 5;
    
            System.out.println("\n1. Half Pyramid\n");
            for (int i = 0; i < rows; i++) {
    
                for (int j = 0; j <= i; j++) {
                    System.out.print("*");
                }
    
                System.out.println("");
            }
    
            System.out.println("\n2. Full Pyramid\n");
            for (int i = 0; i < rows; i++) {
    
                for (int j = 0; j < rows - i; j++) {
                    System.out.print(" ");
                }
    
                for (int k = 0; k <= i; k++) {
                    System.out.print("* ");
                }
    
                System.out.println("");
            }
    
            //java 8 , one line
            System.out.println("\n3. Full Pyramid (Compact)\n");
            for (int i = 0; i < rows; i++) {
    
                System.out.println(String.join("", Collections.nCopies(5 - i - 1, " "))
                        + String.join("", Collections.nCopies(2 * i + 1, "*")));
    
            }
    
            // java 8
            System.out.println("\n4. Inverted Pyramid\n");
            for (int i = rows; i > 0; i--) {
    
                System.out.println(String.join("", Collections.nCopies(5 - i, " "))
                        + String.join("", Collections.nCopies(2 * i - 1, "*")));
    
            }
    
        }
    
    }

输出量

1. Half Pyramid
    
    *
    **
    ***
    ****
    *****
    
    2. Full Pyramid
    
         * 
        * * 
       * * * 
      * * * * 
     * * * * * 
    
    3. Full Pyramid (Compact)
    
        *
       ***
      *****
     *******
    *********
    
    4. Inverted Pyramid
    
    *********
     *******
      *****
       ***
        *

## 参考文献 ##

1.  [Collections.nCopies JavaDoc][]
2.  [Python –打印金字塔][Python]

标签： [Java][] [Java8][] [pyramid][]

> 翻译自: [https://mkyong.com/java/java-how-to-print-a-pyramid/][https_mkyong.com_java_java-how-to-print-a-pyramid]

[Collections.nCopies JavaDoc]: https://docs.oracle.com/javase/8/docs/api/java/util/Collections.html#nCopies-int-T-
[Python]: http://www.mkyong.com/python/python-how-to-print-a-pyramid/
[Java]: https://mkyong.com/tag/java/
[Java8]: https://mkyong.com/tag/java8/
[pyramid]: https://mkyong.com/tag/pyramid/
[https_mkyong.com_java_java-how-to-print-a-pyramid]: https://mkyong.com/java/java-how-to-print-a-pyramid/