hdu u Calculate e

点击打开链接  密码：syuct

u Calculate e

Time Limit : 2000/1000ms (Java/Other)   Memory Limit : 65536/32768K (Java/Other)

Total Submission(s) : 4   Accepted Submission(s) : 2

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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 11 22 2.53 2.6666666674 2.708333333

水题，但是注意小数，是11.9，这个格式。

#include<cstdio>#include<cstring>#include<iostream>using namespace std;#define ll long longint fun(int x){    if(x==1)        return 1;    else        return x*fun(x-1);}int main (){    double s[15]={0};    s[0]=1;    s[1]=2;    s[2]=2.5;    for(int i=3;i<=9;i++)    {        s[i]=s[i-1]+1.0/fun(i);    }    printf("n e\n");    printf("- -----------\n");    printf("0 1\n");    printf("1 2\n");    printf("2 2.5\n");    for(int i=3;i<=9;i++)    {        printf("%d %11.9lf\n",i,s[i]);    }    return 0;}