题目来源：Light OJ 1234 Harmonic Number

题意：

思路：没思路啊 这个是高数的东西 发散 n足够大时它无穷大 直接公式解

#include 
  
   
#include 
   
     #include 
    
      #include 
     
       #include 
      
        #include 
       
         using namespace std; const int maxn = 1000010; const double phi = 0.57721566490153286060651209; double a[maxn]; int main() { for(int i = 1; i <= 1000000; i++) a[i] = a[i-1] + 1.0/i; int cas = 1; int T; scanf("%d", &T); while(T--) { int n; scanf("%d", &n); double ans; if(n <= 1000000) ans = a[n]; else ans = log(n+0.5) + phi; printf("Case %d: %.10lf\n", cas++, ans); } return 0; }