國雄教學.c

//
//  main.c
//  test
//
//  Created by Bob Chang on 2019/3/2.
//  Copyright © 2019 Bob Chang. All rights reserved.
//

#include <stdio.h>

void Test(int **ptr){
    int Bb;
    Bb = 2;
    *ptr = &Bb;
}

int main(int argc, const char * argv[]) {
  
    typedef unsigned char  UINT8;
    typedef unsigned short UINT16;
    typedef unsigned int   UINT32;
    
    // insert code here...
    
    typedef union{
        UINT32 a;
        
        struct aa{
            UINT16 b;
            UINT16 c;
        }aa;
        
        struct bb{
            UINT8 d;
            UINT8 e;
            UINT8 f;
            UINT8 g;
        }bb;
      
    }test;
    
    test tt;
    
    tt.a = 0x12345678;
    
    printf("a = %x, b = %x, c = %x, d= %x, e = %x, f = %x, g = %x\n",tt.a, tt.aa.b, tt.aa.c, tt.bb.d, tt.bb.e, tt.bb.f, tt.bb.g);
    // Output: a = 12345678, b = 5678, c = 1234, d= 78, e = 56, f = 34, g = 12
  
    return 0;
}