为啥输出不了，泰勒公式

Question

# include # include # include using namespace std; int fac(int x) { register int i,f=1; for(i=1;i<=x;i++) f*=i; return f; } int main() { double x,sum=0,c; double i=0; cin>>x; c=x; for(i=0;;i++) { x=(pow(c,2*i+1)*pow(-1,i))/fac(2*i+1); sum=sum+x; if(abs((pow(c,2*i+1)*pow(-1,i))/fac(2*i+1))<1e-6) break; } cout << fixed << setprecision(5) << sum; return 0; }

Answer 1

#include <stdio.h>
#include <math.h>
double fact(int n)
{
  if (n == 0)
  return 1;
  return fact(n - 1)*n;
}
int main()
{
  double x, sum = 0, term = 1;
  int n = 1, t = 1;
  scanf("%lf", &x);
  while (term >= 1e-5) {
  term = pow(x, 2 * n - 1) / fact(2 * n - 1);
  sum += t * term;
  t = -t;
  n++;
 }
  printf("%.3lf\n%d", sum, n - 1);
  return 0;
}