データ構造とc言語

1197 ワード

1.pointer
int y = 1;   //variable y will  live in the globals section, address is 1,000,000. And values is 1.
int main() {
    int x = 4;  //variable x will  live in the stack section, address is 4,100,000. And values is 4.
    return 0;
}
printf("x is stored at %p
", &x); // 「0x3E8FA0」print the address of variable x. This is 4,100,000 in hex (base 16) format. int *address_of_x = &x; printf("x is stored at %p
", address_of_x); // 0x7ffeeddd0ab8 printf("x is at %d
", *address_of_x); // 4 *address_of_x = 99; // reset value
2.struct:
//  1. 
struct fish{
  const char *name;
  int age;
};
struct fish snappy = {"Snappy", 78};

//  2. 「     typedef」
typedef struct fish{
  const char *name;
  int age;
};
struct fish snappy = {"Snappy", 78};

//  3. 「  : struct      FI,  :FI == struct fish」
typedef struct fish{
  const char *name;
  int age;
}FI;
FI snappy = {"Snappy", 78};

//   :
void catalog(struct fish sh){
    printf("%s . His age is %i
",sh.name , sh.age ); } int main() { printf("%d
", snappy.age); catalog(snappy); return 0; }