Summary of Pointers and Arrays adopted from KNK

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Summary of Pointers and Arrays adopted from KNK C Programming : A Modern Approach

Summary of Pointers and Arrays adopted from KNK C Programming : A Modern Approach

배열 되짚어 보기 • 배열: 같은 형의 값을 여러 개 저장할 수 있는 것과

배열 되짚어 보기 • 배열: 같은 형의 값을 여러 개 저장할 수 있는 것과 그것의 시작 주소 int foo[]= {380, 800, 777}; 주소 변수명 0 x 00 c 777 foo[2] 0 x 008 800 foo[1] 0 x 004 380 foo[0] foo 0 x 000 Copyright © 2008 W. W. Norton & Company. All rights reserved. 4

배열: 포인터와의 관계 int foo[]= {380, 800, 777}; 주소 변수명 변수의 시작 주소를 사용한

배열: 포인터와의 관계 int foo[]= {380, 800, 777}; 주소 변수명 변수의 시작 주소를 사용한 변환 0 x 00 c 777 foo[2] foo + 2 x 4 byte 0 x 008 800 foo[1] foo + 1 x 4 byte 0 x 004 380 foo[0] 0 x 000 foo + 0 x 4 byte 기준 위치로 부터 X만큼 떨어진 위치를 접근할 수 있음 Copyright © 2008 W. W. Norton & Company. All rights reserved. 7

포인터의 덧셈과 뺄셈 int foo[]= {10, 20, 30, 40, 50, 70, 80}; Address 0

포인터의 덧셈과 뺄셈 int foo[]= {10, 20, 30, 40, 50, 70, 80}; Address 0 x 00 0 x 04 0 x 08 0 x 0 c 0 x 10 0 x 14 0 x 18 foo 10 20 30 40 50 60 70 80 foo[0] foo[1] foo[2] foo[3] foo[4] foo[5] foo[6] foo[7] index Copyright © 2008 W. W. Norton & Company. All rights reserved. 9

포인터의 덧셈과 뺄셈 int foo[]= {10, 20, 30, 40, 50, 70, 80}; int *p,

포인터의 덧셈과 뺄셈 int foo[]= {10, 20, 30, 40, 50, 70, 80}; int *p, *q; 0 xc 8 0 xe 8 p q Address 0 x 00 0 x 04 0 x 08 0 x 0 c 0 x 10 0 x 14 0 x 18 foo 10 20 30 40 50 60 70 80 foo[0] foo[1] foo[2] foo[3] foo[4] foo[5] foo[6] foo[7] index Copyright © 2008 W. W. Norton & Company. All rights reserved. 10

포인터의 덧셈과 뺄셈 int p = q = foo[]= {10, 20, 30, 40, 50,

포인터의 덧셈과 뺄셈 int p = q = foo[]= {10, 20, 30, 40, 50, 70, 80}; *p, *q; &foo[3]; p + 2; 0 xc 8 0 xe 8 0 x 0 c 0 x 10 p q Address 0 x 00 0 x 04 0 x 08 0 x 0 c 0 x 10 0 x 14 0 x 18 foo 10 20 30 40 50 60 70 80 foo[0] foo[1] foo[2] foo[3] foo[4] foo[5] foo[6] foo[7] index Copyright © 2008 W. W. Norton & Company. All rights reserved. 11

포인터의 덧셈과 뺄셈 int foo[]= {10, 20, 30, 40, 50, 70, 80}; int *p,

포인터의 덧셈과 뺄셈 int foo[]= {10, 20, 30, 40, 50, 70, 80}; int *p, *q; p = &foo[3]; q = p + 2; 0 xc 8 p -= 2; 0 xe 8 0 x 04 0 x 10 p q Address 0 x 00 0 x 04 0 x 08 0 x 0 c 0 x 10 0 x 14 0 x 18 foo 10 20 30 40 50 60 70 80 foo[0] foo[1] foo[2] foo[3] foo[4] foo[5] foo[6] foo[7] index Copyright © 2008 W. W. Norton & Company. All rights reserved. 12

포인터의 덧셈과 뺄셈 int p = q = foo[]= {10, 20, 30, 40, 50,

포인터의 덧셈과 뺄셈 int p = q = foo[]= {10, 20, 30, 40, 50, 70, 80}; *p, *q; &foo[5]; &foo[2]; printf(“%d”, p – q); 0 xc 8 0 xe 8 0 x 10 0 x 08 p q Address 0 x 00 0 x 04 0 x 08 0 x 0 c 0 x 10 0 x 14 0 x 18 foo 10 20 30 40 50 60 70 80 foo[0] foo[1] foo[2] foo[3] foo[4] foo[5] foo[6] foo[7] index Copyright © 2008 W. W. Norton & Company. All rights reserved. 13

Example of Array Processing with Pointers #define N 10 … int a[N], sum, *p;

Example of Array Processing with Pointers #define N 10 … int a[N], sum, *p; … sum = 0; for (p = &a[0]; p < &a[N]; p++) sum += *p; Copyright © 2008 W. W. Norton & Company. All rights reserved. 14

연산자의 결합 (exercise) Expression Meaning *p++ or *(p++) (*p)++ *++p or *(++p) ++*p or

연산자의 결합 (exercise) Expression Meaning *p++ or *(p++) (*p)++ *++p or *(++p) ++*p or ++(*p) Copyright © 2008 W. W. Norton & Company. All rights reserved. 16

배열을 함수의 인자로 전달 Copyright © 2008 W. W. Norton & Company. All rights

배열을 함수의 인자로 전달 Copyright © 2008 W. W. Norton & Company. All rights reserved. 17

함수 인자로 배열은 포인터처럼 동작 • 의미 4: • 배열의 일부만 전달 할 수

함수 인자로 배열은 포인터처럼 동작 • 의미 4: • 배열의 일부만 전달 할 수 있음 int gon(int bar[], int n){ bar[1]++; } int main(void){ int foo = 10; int baz[10] = {0}; } gon(&baz[5], 3); Copyright © 2008 W. W. Norton & Company. All rights reserved. 21

Pointers to pointers multidimensional arrays Pointers to pointersPointers to pointers multidimensional arrays Pointers to pointers
Pointers to pointers multidimensional arrays Pointers to pointersPointers to pointers multidimensional arrays Pointers to pointers
Pointers adopted from KNK C Programming A ModernPointers adopted from KNK C Programming A Modern
Arrays adopted from KNK C Programming A ModernArrays adopted from KNK C Programming A Modern
Pointers n n n Pointers and Arrays PointersPointers n n n Pointers and Arrays Pointers
Arrays Records and Pointers Arrays Records and PointersArrays Records and Pointers Arrays Records and Pointers
Pointers and Arrays 1 Pointers and Arrays nPointers and Arrays 1 Pointers and Arrays n
Arrays The concept of arrays Using arrays ArraysArrays The concept of arrays Using arrays Arrays
Arrays The concept of arrays Using arrays ArraysArrays The concept of arrays Using arrays Arrays
ARRAYS Variable Arrays Control Arrays Dynamic Variable ArraysARRAYS Variable Arrays Control Arrays Dynamic Variable Arrays
Functions adopted from KNK C Programming A ModernFunctions adopted from KNK C Programming A Modern
Control Flow adopted from KNK C Programming AControl Flow adopted from KNK C Programming A
Formatted InputOutput adopted from KNK C Programming AFormatted InputOutput adopted from KNK C Programming A
Selection Statment adopted from KNK C Programming ASelection Statment adopted from KNK C Programming A
C Fundamentals adopted from KNK C Programming AC Fundamentals adopted from KNK C Programming A
C Pointers Systems Programming Pointers Pointers and AddressesC Pointers Systems Programming Pointers Pointers and Addresses
POINTERS AND DYNAMIC MEMORY ALLOCATION POINTERS Pointers featurePOINTERS AND DYNAMIC MEMORY ALLOCATION POINTERS Pointers feature
Pointers n Class 9 Pointers Pointers n nPointers n Class 9 Pointers Pointers n n
Pointers to pointers Plab 2003 Exercise 4 PointersPointers to pointers Plab 2003 Exercise 4 Pointers
Plab Tirgul 5 pointers to pointers libraries PointersPlab Tirgul 5 pointers to pointers libraries Pointers