Java - 다양한 FOR문 예제

 

 

• 2중 for문을 이용하여 직사각형 별찍기

class Solution {
    public static void main(String[] args) {
      
        int a = 5;
        int b = 3;
        
        for(int j=0;j<b;j++){
            for(int i=0; i<a ; i++){
                System.out.print("*");
            }
            System.out.println("");
        }
    }
}

================결과===================

*****
*****
*****

 

 

 

 

• for문을 이용하여 int 배열 값 증가시키기

class Solution {
    public long[] solution() {
    	int x=2;
        int n=5;
        long[] answer = new long[n];
        for(int i=0; i<n; i++){
            long a = (long)x*(i+1);
            answer[i]= a;
        }
        return answer;
    }
}

======결과===================================
[2, 4, 6, 8, 10]

 

 

• 2중 for문을 이용하여 2차 배열의 합 구하기 

class Solution {
    public int[][] solution() {
    	int[][] arr1=[[1, 2], [2, 3]];
    	int[][] arr2=[[3, 4], [5, 6]];
        int[][] answer = arr1;       
        
        for(int i=0; i<arr1.length; i++){
             for(int j=0; j<arr1[i].length; j++){
                 answer[i][j]=arr1[i][j]+arr2[i][j];
             }
        }    
        return answer;
    }
}

=================================결과=========================================
	[[4, 6], [7, 9]]