2

 1 #include<cstdio>
 2 #include<cstdlib>
 3 #include<cmath>
 4 #include<iostream>
 5 using namespace std;
 6 
 7 long double a=-5.8522e+04,b=3.7519e+11,c=6.8944e-07,g0=9.7803,
 8     gama=1.4000,k=0.00046,P0=101325,P00=101325.0,Re=6378137.0,
 9     rou0=1.2250,rou00=1.1031865,T0=273.0,T00=303.1500,
10     mu=0.027441,R=8.3140,A=58857.2530,B=375399623239.3531;
11 long double n0=pow(1+k*c*(a+b/Re),2.5);
12 
13 long double phi()
14 {
15     int n=10000;
16     long double st=1,ed=1+k*rou00;
17     long double delta=(ed-st)/n,ans=0;
18     for(int i=1;i<=n;i++)
19     {
20         long double X=(st-1)*pow(T00,3.5)/k/rou0/T0;
21         long double H=pow(X,0.4)+A-303.15;
22         H=B/H;
23         H-=6378137;
24         ans+=n0*Re/st/(Re+H)/
25         sqrt(1-(n0*Re/st/(Re+H))*(n0*Re/st/(Re+H)))/st*delta;
26         st+=delta;
27     }
28     return ans;
29 }
30 
31 long double eps=1e-8,tar=0.0098901991;
32 long double tdiv()
33 {
34     long double l=0.0,r=1.0;
35     while(r-l>eps)
36     {
37         long double mid=(l+r)/2;k=mid;
38         long double ans=phi();
39         if(ans<tar) l=mid;
40         else r=mid;
41     }
42     return l;
43 }
44 
45 int main()
46 {
47     long double ans=phi();
48     tdiv();
49     return 0;
50 }