2018-10-05

#include <iostream>

#include <iomanip>

using namespace std;

int main()

{double fuc(int x);

double a,b=1;

a=fuc(b);

cout<<setprecision(10)<<"e="<<a;

return 0;

}

double fuc(int x)

{double p=1,q=1,sum=1;

while (p>=0.1e-10)

{double y=1,i=1;

    while (i<=x)

      {y=i*y;

      i++;

      }

  p=q/y;

  sum=sum+p;

  x++;

}

return(sum);

}