matrixmulti.java

用netbean编写的矩阵乘法和计算多个圆环面积之和

/*
 * 实验4－题目3
 */

public class MatrixMulti {

    public static void main(String[] args) {
        int a[][] = {{1, 1, 1}, {1, 1, 1}};
        int b[][] = {{1, 1}, {1, 1}, {1, 1}};

        int c[][] = multiplyMatrix(a, b);

        for (int i = 0; i < c.length; i++) {
            for (int j = 0; j < c[i].length; j++) {
                System.out.print(c[i][j] + " ");
            }
            System.out.println("");
        }
    }

    public static int[][] multiplyMatrix(int[][] a, int[][] b) {
        if (a[0].length != b.length) {
            return null;
        }

        int[][] c = new int[a.length][b[0].length];
        for (int r = 0; r < a.length; r++) {
            for (int k = 0; k < b[r].length; k++) {
                c[r][k] = 0;
                for (int i = 0; i < a[r].length; i++) {
                    c[r][k] += a[r][i] * b[i][k];
                }
            }
        }

        return c;
    }
}