对称矩阵与压缩存储算法（java实现）

package 数组和矩阵;

public class DuiChenJuZhenYaSuo {

	int[] arr;

	int order; //矩阵的阶数

	int n; //压缩后一位数组的个数

	public DuiChenJuZhenYaSuo(int order) {

		this.n= order * (order + 1) / 2;

		this.arr = new int[this.n];

		this.order = order;

	}

	public void init(int[][] a) {

		int k = 0;

		for (int i = 0; i < order; i++) {

			for (int j = 0; j <= i; j++) {

				arr[k++] = a[i][j];

			}

		}

	}

	public void init(int[] a) {

		for (int i = 0; i < n; i++) {

			arr[i] = a[i];

		}

	}

	public void print() {

		int k;

		for (int i = 1; i <= order; i++) {

			for (int j = 1; j <= order; j++) {

				k= (i >= j) ? (i * (i - 1) / 2 + j - 1) : (j * (j - 1) / 2 + i - 1);

				System.out.print(arr[k] + " ");

			}

			System.out.println();

		}

	}

	public DuiChenJuZhenYaSuo merge(DuiChenJuZhenYaSuo a) {

		DuiChenJuZhenYaSuo test = new DuiChenJuZhenYaSuo(this.order);

		int k;

		for (int i = 1; i <= order; i++) {

			for (int j = 1; j <= order; j++) {

				k = (i >= j) ? (i * (i - 1) / 2 + j - 1) : (j * (j - 1) / 2 + i - 1);

				test.arr[k] = this.arr[k] + a.arr[k];

			}

		}

		return test;

	}

	public static void main(String[] args) {

		DuiChenJuZhenYaSuo test = new DuiChenJuZhenYaSuo(3);

		DuiChenJuZhenYaSuo test2 = new DuiChenJuZhenYaSuo(3);

		int[][] a = { { 1, 0, 0 }, { 2, 3, 0 }, { 4, 5, 6 } };

		int[] b= {1,2,3,4,5,6};

		test.init(b);

		test2.init(a);

		test = test.merge(test2);

		test.print();

	}

}