高斯消元（附BZOJ - 1013 球形空间产生器代码）

Gaussian-Elimination.cpp

@@ -0,0 +1,48 @@
+#include <cstdio>
+
+using namespace std;
+
+int n;
+double a[15][15], s[15];
+
+void gaussian_elimination()
+{
+	for (int i = 0; i < n; i++)
+	{
+		for (int j = i + 1; j < n; j++)
+		{
+			for (int k = n; k >= i; k--)
+			{
+				a[j][k] -= a[i][k] * (a[j][i] / a[i][i]);
+			}
+		}
+	}
+	for (int i = n - 1; i >= 0; i--)
+	{
+		double b = a[i][n];
+		for (int j = n - 1; j > i; j--)
+		{
+			b -= a[i][j] * s[j];
+		}
+		s[i] = b / a[i][i];
+	}
+}
+
+int main()
+{
+	scanf("%d", &n);
+	for (int i = 0; i < n; i++)
+	{
+		for (int j = 0; j < n; j++)
+		{
+			scanf("%lf", &a[i][j]);
+		}
+		scanf("%lf", &a[i][n]);
+	}
+	gaussian_elimination();
+	for (int i = 0; i < n; i++)
+	{
+		printf("x[%d] = %.2lf\n", i, s[i]);
+	}
+	return 0;
+}