c++自动推导类型auto

#include "iostream"

using namespace std;

string func(){
    return "西施";

}

double func1(int a,double b,const char *c,float d,short e,long f){
    cout<<"a="<<a<<",b="<<b<<",c="<<c<<",e="<<e<<",f="<<f<< endl;
    return 5.5;
}

int main(){
    auto a=3+1;cout<<"a="<<a<<endl;
    auto b=3.3+a;cout<<"b="<<b<<endl;
    auto c="西施";cout<<"c="<<c<<endl;
    auto d=func();cout<<"d="<<d<<endl;
    double (*pf)(int ,double ,const char*,float ,short ,long );
    pf=func1;
    pf(1,2,"西施",3,4,5);
    auto pf1= func1;
    pf1(1,2,"西施",3,4,5);
}

输出:a=4
b=7.3
c=西施
d=西施
a=1,b=2,c=西施,e=4,f=5
a=1,b=2,c=西施,e=4,f=5