[数据结构-严蔚敏版]P95矩阵压缩-特殊矩阵的存储(对称矩阵，三角矩阵)

Posted 2021-09-06 Wecccccccc

对称矩阵的存储：

代码如下:

#include <iostream>
using namespace std;

int main()
{
	int n;
	cin >> n;
	int *a;
	a = new int[(n*(n + 1)) / 2];
	for (int i = 0; i < (n*(n + 1)) / 2; i++)
	{
		cin >> a[i];
	}
	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= n; j++)
		{
			if (i >= j)
			{
				int idx = (i*(i - 1)) / 2 + (j - 1);
				cout << a[idx] << " ";
			}
			else
			{
				int idx = (j*(j - 1)) / 2 + (i - 1);
				cout << a[idx] << " ";
			}
		}
		cout << endl;
	}
	return 0;
}

三角矩阵的存储:

代码如下:

#include <iostream>
using namespace std;

int main()
{
	int *a;
	int n;
	cin >> n;
	int N = ((n*(n + 1)) / 2) + 1;
	a = new int[N];
	for (int i = 0; i < N; i++)
	{
		cin >> a[i];
	}
	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= n; j++)
		{
			if (i >= j)
			{
				int idx = (i*(i - 1)) / 2 + (j - 1);
				cout << a[idx] << " ";
			}
			else
			{
				cout << a[N - 1] << " ";
			}
		}
		cout << endl;
	}
	return 0;
}