Thread: Help With While Loop

Hey guys, I need some help.
I have to find the sum of all the terms up to the nth term that I choose.
I can't figure out how to construct a while loop for it though? I am a rookie doing this so sorry if its a dumb question. Anything helps.
Thanks in advance.

Code:

#include<stdlib.h>
#include<stdio.h>


int fact;
int factorial(int n);


int power(float,int);
int Power(int,int);


int main()
{
    int i, n;
    float x, FS, NT, SS;
printf("The Series is 1 - 2(x^2)/1! + 3(x^4)/2! - 4(x^6)/3! +....+ [(-1)^n)](n+1)(x^2n)/n!\n");// Series Provided
printf("What is you value for n and x, respectively:\n");// Input n and x
    scanf("%d %f", &n, &x);
printf("Your inputs for n and x were\nn=%d\nx=%f\n", n, x);

    FS=1;// FS = First Term from Series
    NT=(power(-1,n)*(n+1)*power(x,2*n))/factorial(n);// NT = Nth Term
    SS=1;// SS = Series Sum
    i=1;

    while(i<=n)//loop
    {
        FS=FS+NT;
        SS=SS+FS;
        i=i+1;
    }

printf("The result is %f\n", NT);

    system("pause");
    return 0;
}


int factorial(int n)// Factotial function
{
    if(n==1)
    {
        return 1;
    }
    else
    {
        fact = n * factorial(n-1);
        return fact;
    }


}


int power (float x, int n)// Exponent Function
{
    int i, var=x;
    if (n==0) return 1;
    for (i=1; i<n; i++)
        x*=var;
    return x;
}