20201014_ 15 2차원배열 겉에 외곽선네모합구하기

 

public class Sample4 {

	public static void main(String[] args) {
		int sum = 0;
		int count = 1;
		int[][] a = new int[5][5];
		
		for (int i = 0; i < a.length; i++) {
			for (int j = 0; j < a.length; j++) {
				a[i][j] = count;
				count ++;
				System.out.printf("%4d" ,a[i][j]);
			}
			System.out.println(" ");
		}
		for (int i = 0; i < a.length; i++) {
			for (int j = 0; j < a.length; j++) {
				if (i== 0 || i ==4|| j==0 || j ==4) {
					sum += a[i][j];
					System.out.println(a[i][j]);
				}
			}
		}
		System.out.println(sum);
	}
}

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