u Calculate e
问题陈述:
杭州电子科技大学 HANGZHOU DIANZI UNIVERSITY Online Judge Problem - 1012
问题解析:
简单题,注意输出格式。引入<iomainip>头文件,调用setprecision()函数设置精度。
代码详解:
1 #include <iostream> 2 #include <iomanip> 3 #include <cstdio> 4 5 using namespace std; 6 7 int factorial(int); 8 9 int main() 10 { 11 int i, n; 12 double e; 13 cout << "n" << " " << "e" << endl; 14 cout << "-" << " " << "-----------" << endl; 15 for(n=0; n<=9; n++) { 16 e = 0; 17 for(i=0; i<=n; i++) { 18 e += 1.0/factorial(i); 19 } 20 if(n < 3) { 21 cout << n << " " << e << endl; 22 }else { 23 cout << fixed << setprecision(9) << n << " " << e << endl; 24 } 25 } 26 return 0; 27 } 28 29 int factorial(int n) { 30 if(n == 0) { 31 return 1; 32 }else { 33 return n * factorial(n-1); 34 } 35 }