这个程序描述的是利用e^x的展开式求e^x，但是为什么结果总错误😭

#include
int main() {
double x; int n = 1; long double sum = 0; double k = 1; double i; double j = 0;
scanf_s("%lf", &x);
while (n <= 100) {
int N = 1;
while (N <= n) {
k = k * ( double)((double)x / (double)N);
N++;
}
sum = (double)sum+(double)k;
n++;
}
printf("%.2lf", sum);
return 0;
}

你这x没有初始化