c++ - 同样的源代码在visual studio能正确执行，g++运行结果有问题？
追赶法解线性方程组。
代码如下：
#include <iostream>
#include <cmath>
using namespace std;
void MyAlgorithm(double a[], double b[], double c[], double d[], int size)
{
if (abs(b[0]) > abs(c[0]) && abs(c[0]) > 0 &&
abs(b[size - 1]) >= abs(a[size - 1]) && abs(a[size - 1]) > 0)
{
int i;
for (i = 1; i != size - 1; ++i)
{
if (abs(b[i]) < abs(a[i]) +abs(c[i]) ||
a[i] * c[i] == 0)
{
cout << "不满足追赶法条件！" << endl;
return;
}
}
for (i = 1; i != size; ++i)
{
a[i] = a[i] / b[i - 1];
b[i] = b[i] - a[i] * c[i - 1];
d[i] = d[i] - a[i] * d[i - 1];
}
d[size] = d[size] / b[size];
for (i = size - 1; i != -1; --i)
{
d[i] = (d[i] - c[i] * d[i + 1]) / b[i];
}
}
else cout << "不满足追赶法条件！" << endl;
return;
}
int main(int argc, char const *argv[])
{
double a_0[4] = { 0, -1, -1, -1 };
double b_0[4] = { 2, 2, 2, 2 };
double c_0[4] = { -1, -1, -1, 0 };
double d_0[4] = { 5, -12, 11, -1 };
int i;
MyAlgorithm(a_0, b_0, c_0, d_0, sizeof(a_0) / sizeof(double));
for (i = 0; i != sizeof(a_0) / sizeof(double); ++i)
{
cout << "x_" << i + 1 << '\t' <<d_0[i] << endl;
}
cout << endl;
return 0;
}使用vs 2015能输出正确结果，而g++编译则为nan。。。
发现第27行会改变c[0]值。。。不懂。。。
求问。
