Computer Programming in C Chapter 6

1. Computer Programming in C Chapter 6 2013년 가을학기 부산대학교 정보컴퓨터공학부

2. 6장. Structure • 목차 • Structure 기본 개념 • Typedef • Pointer to Structure • Structure Array • Structure를 이용한 Function Parameter • Union • Bitwise Structure Computer Programming Chapter 6

3. 1. Structure의 기본 개념 • 복합적인 데이터 • Example: • StudentScore, StudentName, StudentYear… • Structure의 이용 int studentScore[100];int studentYear[100]; char *studentName[100] structure의 member 표지 struct student { int score; int year; char name[50]; }; struct student students[100]; students[i].score=40; students[i].year=4; strcpy(student[i].name,”Lik”); Computer Programming Chapter 6

4. 2. Typedef • Typedef • User-Defined Type : cf. Built-in Type • More convenient than struct struct student { int score; int year; char name[50]; }; struct student students[100]; New type typedef struct { int score; int year; char name[50]; } student; student students[100]; Computer Programming Chapter 6

5. 3. Pointer to Structures • Pointer to Structures • Structure Types의 변수가 저장된 주소 typedef struct { int score; int year; char name[50]; } student; student *pstudent; pstudent=malloc(10*sizeof(student)); for(i=0;i<10;i++) { pstudent->year=0; pstudent->score=0; pstudents++; } structure의 member 표시 student students[100]; pstudent=students; for(i=0;i<10;i++) { pstudent->year=0; pstudent->score=0; pstudents++; } student students[100]; pstudent=students; for(i=0;i<10;i++) { pstudent[i].year=0; pstudent[i].score=0; } Computer Programming Chapter 6

6. 4. Structure Array • 다른 Type과 같이 Array 가능 typedef struct { int score; int year; char name[50]; } student; student students[]= { {3.0, 1, “WG-1”}, {3.5, 1, “WG-2”}, {2.9, 1, “WB-1”}}; struct student { int score; int year; char name[50]; }; struct student students[3]; student *pstud; pstud=students;for(i=0i<3;i++){ pstud->year=0; pstud->score=0.0; pstud++;} for(i=0i<3;i++){ students[i].year=0; students[i].score=0.0;} Computer Programming Chapter 6

7. 5. Struct와 Function Parameter • Structure를 이용한 Function의 Parameter • 매우 단순 • typedef는 가능한 header file에 정의 • Structure Pointer를 이용한 Function Parameter float Vector10Norm(float v1, float v2, float v3, …, v10) float Vector10Norm(struct vector10 vector) void inputStudent(student *s) { s->year=3; s->score=3.56; strcpy(s->name,”WG-2”); } inputStudent(student &stud); Computer Programming Chapter 6

8. 6. Union • 경우에 따라 다른 Type을 가지는 것의 Wrapping • Sizeof(Union): 가장 큰 size에 의하여 결정 typedefstruct { char name[50]; int age; char status; /* 0: student, 1: prof. */ union { unsigned int year; /* for student */ char position[20]; /* for professor */ } level;} UnivPerson; UnivPersona; a.status=0; s.level.year=0; Computer Programming Chapter 6

9. 7. Bitwise Operation • Bit 단위로 변수를 사용 • Structure Type을 이용 typedef struct { unsigned short year:2; /* 00:1, 01:2, 10:3, 11:4 */ unsigned short gender:1; /* 1: female, 0: male */ unsigned short dept:5; /* 000: phy, 001: chem ... */ } studentStatus; Computer Programming Chapter 6

10. Mask 이용 #define Mask_Year 0x0003 /* 0000 0000 0000 0011 */#define Mask_Gender 0x0004 /* 0000 0000 0000 0100 */ #define Mask_Dept 0x0038 /* 0000 0000 0011 1000 */ #define Male 0x0000#define Female 0x0004 unsigned short studentStatus;studentStatus = (studentStatus & ~Mask_Gender) | Male; . . . if (studentStatus & MaskGender == Male) ... Computer Programming Chapter 6