编写一个程序，有一分数序列：2/1，3/2，5/3，8/5，13/8，21/13...求出这个数列

编写一个程序，有一分数序列：2/1，3/2，5/3，8/5，13/8，21/13...求出这个数列

#include
#include
int func(int n)
{
if(n==1)return 1;

else if(n==2)return 2;

else return func(n-1)+func(n-2);

}
int main()
{
int i;

double sum=0;

int a[20],b[20];

for(i=0;i<20;i++)
{
a[i]=func(i+1);
b[i]=func(i+2);

sum += (double)b[i]/(double)a[i];

}
printf("sum=%lf\n",sum);

system("pause");

return 0;

}

Private Sub Command1_Click()
Dim i%, k%, l%, t5
Dim n As Single
k = 1
l = 1
T = 1
For i = 1 To 20
l = l + T

n = n + l / k
T = k
k = l
Next
Print n
End Sub

示例代码：(省略了main)
float sum = 0; //最终结果值

float num1 = 2;
float num2 = 1;
float lastNum2 = 1;
for(int i = 1; i <= 20; ++i)
{
sum = sum + num1 / num2;
if(i == 1)
{
num1 = 3;
num2 = 2;
}else
{
num1 = num1 + num2;
float oldNum2 = num2;
num2 = lastNum2 + num2;
lastNum2 = oldNum2 ;
}
}
printf("%f", sum );