---
# System prepended metadata

title: CS61B HW0 - Drawing a Triangle
tags: [Practice, Java]

---

# CS61B HW0 - Drawing a Triangle

###### tags: `Java` `Practice`

Creative Exercise 1a: Drawing a Triangle
Draw Triangle using while
```
package cs61b;

public class DrawTriangle {

	public static void main(String[] args) {
		int row = 0;
		int SIZE = 5;
		
		while (row < SIZE) {
			int col = 0;
			while (col <= row) {
			System.out.print("*");
			col = col + 1;
			
			}
			System.out.println();
			row = row + 1;	
		}
		
	}

}
```
1. column每loop一次都要先歸零，才會在首項打點
2. 換行之後要先print新的一行，row才能加1以開啟新的row

執行步驟展示：
https://cscircles.cemc.uwaterloo.ca/java_visualize/#mode=edit

---

Creative Exercise 1b: method "drawTriangle"
將畫三角形變成一個方法讓main去呼叫

```
package cs61b;

public class DrawTriangleMethod {
	
	public static void drawTriangle (int N) {
		
		int row = 0;
		int SIZE = N;
		
		while (row < SIZE) {
			int col = 0;
			while (col <= row) {
				System.out.print("*");
				col ++;
			}
			System.out.println();
			row++;
		}
	}
	
	

	public static void main(String[] args) {
		drawTriangle(10);

	}

}

```
將size的整數寫在argument中, 之後在呼叫的時候即可直接keyin整數

