[ JAVA ] 별 출력하기 (삼격형, 마름모, 모래시계 등)

1. 삼각형

1.1. 

 

for (int i = 1; i <= 4; i++) {
	for (int j = 1; j <= i; j++) {
		System.out.print("*");
	} //for
	System.out.println();
} //for

 

 

1.2.

for (int i = 1; i <= 4; i++) {
	for (int j = 1; j <= 5-i; j++) {
		System.out.print("*");
	} //for
	System.out.println();
} //for

 

 

1.3.

for (int i = 1; i <= 4; i++) {
	for (int j = 1; j <= 4; j++) {
		if(i>=5-j)  System.out.print("*");
		else 	System.out.print("_");
	} //for
	System.out.println();
} //for

 

1.4.

for (int i = 1; i <= 4; i++) {
	for (int j = 1; j <= 4; j++) {
		if(i<=j)  System.out.print("*");
		else 	System.out.print("_");
	} //for
	System.out.println();
} //for

 

1.5. 행의 갯수를 입력받아 이등변 삼각형 출력

import java.util.Scanner;

public class Ex02 {
	public static void main(String[] args) {
    
		try (Scanner scanner = new Scanner(System.in)) {
			System.out.print("> 행의 갯수 입력?  ");
			int row = scanner.nextInt();
			int col = row*2-1;
            
			for (int i = 1; i <= row; i++) {
				for (int j = 1; j <= col; j++) {
					if (i+j>=row+1 && j-i<=row-1)  System.out.print("*");
					else System.out.print("_");
				} //for col
				System.out.println();
			}  //for row
            
		} catch (Exception e) {
			e.printStackTrace();	//err 메시지 출력
		} //try-catch

	} //main
} //class

 

 

2. 마름모

int size = 3;
for (int i = 1; i <= size; i++) {
	System.out.println("_".repeat(size - i) + "*".repeat(2 * i - 1));
} //for 윗부분

for (int i = size - 1; i >= 1; i--) {
	System.out.println("_".repeat(size - i) + "*".repeat(2 * i - 1));
} //for 아랫부분

 

 

3. 대각선

3.1.

for (int i = 1; i <= 5; i++) {
	for (int j = 1; j <= 5; j++) {
		if(i==j)  System.out.print("*");
		else 	System.out.print("_");
	} //for
	System.out.println();
} //for

 

3.2.

for (int i = 5; i >= 1; i--) {
	for (int j = 1; j <= 5; j++) {
		if(i==j)  System.out.print("*");
		else 	System.out.print("_");
	} //for
	System.out.println();
} //for

 

 

4. X

for (int i = 1; i <= 5; i++) {
	for (int j = 1; j <= 5; j++) {
		if(i==j || i==6-j)  System.out.print("*");
		else 	System.out.print("_");
	} //for
	System.out.println();
} //for

 

 

 

5. 모래시계

for (int i = 1; i <= 5; i++) {
	for (int j = 1; j <= 5; j++) {
		if((i<=j && i<=6-j) || (i>=j && i>=6-j))  System.out.print("*");
		else 	System.out.print("_");
	} //for
	System.out.println();
} //for