27.指针函数的调用

#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
double f1(double x)
{
return x*x;
}
double f2(double x, double y)
{
return x*y;
}
double fun(double a, double b)
{
double(*f)();
double r1, r2;
f = f1;
r1 = f(a);
f = f2;
r2 = (*f)(a, b);
return r1 + r2;
}
int main()
{
double x1 = 5, x2 = 3, r;
r = fun(x1, x2);
printf("\nx1=%f,x2=%f,x1*x1+x1*x2=%f\n", x1, x2, r);
getchar();
return 0;
}