I keep getting an error in my for statement. Syntax error before "double". Please help anyone!!!

#include<stdio.h>

#include<stdlib.h>

#include<math.h>

#include<conio.h>

double factorial(int num); /*function to compute factorial of a no.*/

int main()

{

int terms;

int i;

double eCalc=0; /*to store the calculated value of e*/

double e=2.718281828458;

double difference;

do

{

printf("Enter no. of terms (n): ");

scanf("%d",&terms);

}

while(terms<=0); /*continue to loop until a positive value is entered*/

for(i=0; i<=terms ; i++)

{

eCalc+=double(1)/factorial(i); /*using formula e = 1/0! + 1/1! + 1/2! + ... + 1/n!*/

}

difference = fabs(e - eCalc);

printf("\nThe approximate value of e : %.12f",e);

printf("\nCalculated mathematical constant e : %.12f",eCalc);

printf("\nThe difference is : %.12f",difference);

/*the .12 after the % signs specifies that there are 12 decimal*/

/*places*/

getch();

}

double factorial(int num) /*recursive function to compute factorial*/

{

if(num==1||num==0) /*the factorial of zero is also 1, it's a mathematical rule!*/

{

return 1;

}

/*the control won't reach the following line if the above*/

/*condition becomes true as the 'return' would also exit*/

/*the function*/

return num * factorial(num - 1);

}