The definition and usage of the pointer and function type of typedef function __ function

1, first give an interview question:

#include "stdafx.h"

#include "stdio.h"

Realize the value of the self increase 1

INT Inc (int a)

{

return (++A);

}

To achieve a multiplication of numeric values

Intmulti (INT*A,INT*B,INT*C)

{

return (*C=*A**B);

}

Defines a function type FUNC1, which has an integer parameter that returns an int type data. At this point FUNC2 is a function type.

Typedefint (FUNC1) (int in);

Defines a function type FUNC2, which has three integer pointer parameters, and returns an int type data. At this point FUNC2 is a function type.

typedef int (FUNC2) (int*,int*,int*);

void Show (Func2*fun,int arg1, INT*ARG2)

{

FUNC1 *p=inc; Defines a function pointer to int Inc (int a)

int temp =p (arg1);//temp=arg1+1;

Fun (&TEMP,&ARG1,ARG2); The Fun function type contains three parameters

printf ("%d\n", *arg2);

}

int main (int argc,char* argv[])

{

int A;

Show (Multi,10,&a); Value is 10*11=110

return 0;

}

2, the above code in the

Defines a function type FUNC1, which has an integer parameter that returns an int type data. At this point FUNC2 is a function type.

Typedefint (FUNC1) (int in);

Defines a function type FUNC2, which has three integer pointer parameters, and returns an int type data. At this point FUNC2 is a function type.

typedef int (FUNC2) (int*,int*,int*);

The reference method is:

FUNC1 *p=&inc;

FUNC2 *fun=&multi;

You can also define the form as a function pointer:

Defines a function pointer of type FUNC1, which points to a formal parameter with an int type and returns a function of type int, at which point FUNC1 is a function pointer

Typedefint (*FUNC1) (int in);

Defines a function pointer of type FUNC2, which points to a formal parameter with only three int* types, and returns a function of type int, at which point FUNC2 is a function pointer

typedef int (*FUNC2) (int*,int*,int*);</span>

The reference method is:

FUNC1 p=&inc;

FUNC2 fun=&multi;

3, in the use of the process, the middle bracket remember to use.