#include <iostream>
using namespace std;
 
namespace  A
{
    void f(double x){cout<<"A::f(double)\n";}
 
    void f(string s){cout<<"A::f(string)\n";}
 
    namespace B
    {
        using A::f;
        void f(int x){cout<<"B::f\n";}
 
        void call()
        {
            f(10);  // calls B::f, expected
            f(10.5); // calls B::f, why??
            string s="Hi";
            f(s);  // error, why??
        }
    }
}
 
int main() {
    A::B::call();
	// your code goes here
	return 0;
}

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