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u Calculate e

2016-02-26 22:16  想打架的蜜蜂  阅读(327)  评论(0编辑  收藏  举报

u Calculate e

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 39381    Accepted Submission(s): 17893


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

#include<iostream>
#include<iomanip>
using namespace std;

 

int main()
{
cout<<"n "<<"e"<<endl;
cout<<"- -----------"<<endl;
double e[10]={0};
e[0]=1;
cout<<0<<" "<<fixed<<setprecision(0)<<e[0]<<endl;
for(int i=1;i<10;i++)
{
double temp=1.0*i;
for(int j=i-1;j>0;j--)
{
temp*=j;
}
e[i]=e[i-1]+1/temp;
if(i==1)
{
cout<<i<<" "<<fixed<<setprecision(0)<<e[i]<<endl;
}
else if(i==2)
{
cout<<i<<" "<<fixed<<setprecision(1)<<e[i]<<endl;
}
else
{
cout<<i<<" "<<fixed<<setprecision(9)<<e[i]<<endl;
}
}
return 0;
}