class Program
{
//函数多个返回值
//输入参数前加Out就变成输出参数
public int jisuan(int a, int b, out int c)
{
c = a - b;
return a + b;
}
public int jiefangcheng(int a, int b, int c, out double x1, out double x2)
{
x1 = 0;
x2 = 0;
if (0 == b * b - 4 * a * c)
{
x1 = (-b) / (2 * a);
x2 = x1;
return 1;
}
else if (0 < b * b - 4 * a * c)
{
x1 = (-b + Math.Sqrt(b * b - 4.0 * a * c)) / (2.0 * a);
x2 = (-b - Math.Sqrt(b * b - 4.0 * a * c)) / (2.0 * a);
return 2;
}
else
{
return 0;
}
}