航电1012 u Calculate e

u Calculate e

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 39017    Accepted Submission(s): 17700

Problem Description

A simple mathematical formula for e is



where n is allowed to go to infinity. This can actually yield very accurate approximations of e using relatively small values of n.

 

Output

Output the approximations of e generated by the above formula for the values of n from 0 to 9. The beginning of your output should appear similar to that shown below.

 

Sample Output

n e - ----------- 0 1 1 2 2 2.5 3 2.666666667 4 2.708333333

 

Source

Greater New York 2000

#include<stdio.h>
double mul(double x)
{
    double sum=1;
    for(int i=1;i<=x;i++)
        sum*=i;
    return sum;
}
int main()
{
    int j;
    double i,e=0,k;
    printf("n e
");
    printf("- -----------
");
    printf("0 1
");
    printf("1 2
");
    printf("2 2.5
");
    for(j=0;j<10;j++)
    {
        e+=1/mul(j);
        if(j>2)    printf("%d %11.9f
",j,e);
    }
    return 0;
}