阶乘分之一求和公式C语言,n的阶乘分之一之和

//求n的阶乘分之一的和

int n;

Console.WriteLine("请输入n!");

try

{

n = Convert.ToInt32(Console.ReadLine());

}

catch (Exception ex)

{

throw (ex);

}

float sum = 1;

decimal total = 0;

for (int i = 1; i <= n; i++)

{

sum *= i;

total += 1m/ sum;

Console.WriteLine("递归数"+i+"是"+sum);

}

Console.WriteLine("被一除的和是"+total);

//用递归实现

class F1

{

public decimal F(int n)

{

decimal d;

if (n < 0)

return -1;

if (n == 0 || n == 1)

{

return 1;

}

else

{

d = 1m / n * F(n - 1);

}

return d;

}

}

class Test

{

static void Main()

{

int b;

F1 f = new F1();

do

{

try

{

b = Convert.ToInt32(Console.ReadLine());

}

catch (Exception ex)

{

throw (ex);

}

if (b < 0)

{

Console.WriteLine("你输入的数必须大于等于0！");

}

if (b == 0)

{

Console.WriteLine("1");

}

else

{

decimal a = 0;

while (b > 0)

{

a += f.F(b);

b--;

}

Console.WriteLine(a);

}

} while ("Q" != Console.ReadLine());

}

}