Java开发练习1 求一个n阶方阵对角线元素之和。_seriesgerry的博客

求一个n阶方阵对角线元素之和。

import java.util.*;
public class Fangzhen {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		int n = 0;
		Scanner num = new Scanner(System.in);
		System.out.println("请输入阶数：");
		 n = num.nextInt();
			int[][] a =new int[n][n];
		Scanner reader = new Scanner(System.in);
		System.out.println("请输入元素：");
		for(int i = 0;i<n;i++){
			for(int j = 0;j<n;j++){
				a[i][j] = reader.nextInt();
			}
			
		}
			int nm1,nm2,sum1 = 0,sum2 = 0,sum=0;
			for(int i = 0;i<n;i++){
				nm1 = a[i][i];
				sum1 = sum1 + nm1;
			}
			for(int i = 0,j=n-1;i<n;i++,j--){
				nm2 = a[i][j];
				sum2 = sum2+nm2;
			}
			sum = sum1+sum2;
			System.out.println("对角线上元素之和是"+sum);
		}import java.util.*;
public