Matrix Max Sum Program

Example

Input : 5
           10 13 10 12 15
           12 39 30 23 11
           11 25 50 53 15
           19 27 29 37 27
           19 13 30 13 19
Output : 155

 

My answer:

import java.util.Scanner;

class MatrixMaxSum {
	public static void main(String[] args) {
		MatrixMaxSum t = new MatrixMaxSum();
		Scanner kb = new Scanner(System.in);
		int n = kb.nextInt();
		int[][] a = new int[n][n];
		for(int i = 0; i < n; i++) {
			for(int j = 0; j < n; j++) {
				a[i][j] = kb.nextInt();
			}
		}
		System.out.println(t.solution(n, a));
	}

	int solution(int n, int[][] a) {
		int max = 0;
		for(int i = 0; i < n; i++) {
			int tmp = 0;
			for(int j = 0; j < n; j++) {
				tmp += a[i][j];
			}
			if(tmp > max) max = tmp;
		}
		for(int i = 0; i < n; i++) {
			int tmp = 0;
			for(int j = 0; j < n; j++) {
				tmp += a[j][i];
			}
			if(tmp > max) max = tmp;
		}
		int tmp2 = 0;
		for(int i = 0; i < n; i++) {
			tmp2 += a[i][i];
		}
		if(tmp2 > max) max = tmp2;
		int tmp3 = 0;
		for(int i = 0; i < n; i++) {
			tmp3 += a[i][n-1-i];
		}
		if(tmp3 > max) max = tmp3;
		return max;
	}
}

 

1. Input Reading:
   • It uses a Scanner to read the input.
   • Reads an integer n, representing the size of the square matrix.
   • Reads the elements of the matrix (a) row by row.
2. Matrix Sum Calculation:
   • The solution method calculates the sum of each row and updates the max variable if a larger sum is found.
   • It then calculates the sum of each column and updates max accordingly.
   • The sums of the main diagonal and the secondary diagonal are calculated and compared with max.
3. Output:
   • The final maximum sum is printed to the console.

---

메모장에 완벽하게 설계했고, 재밌게 코딩했는데 결과가 다르게 나와서 당황했다..

'tmp2 += a[i][i];' 를 'tmp2 = a[i][i];' 로 했던 것...

이런 오류는 발견하기 힘드니 꼼꼼하게 코딩해야겠다..