Lec 38.39 - pointers
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The document discusses pointers in C++, including how to access addresses and contents using pointers, how to access array elements using indexes and pointers, and how pointers can be used to pass arguments to functions by reference or by pointer. It also provides examples of pointer usage and briefly describes bubble sort as a sorting algorithm.
![Array Accessing Using Index
int main()
{
int intarray[5] = { 31, 54, 77, 52, 93 };
for(int j=0; j<5; j++)
cout << intarray[j] << endl;
getch();
return 0;
}](https://image.slidesharecdn.com/lec-38-39-pointers-130222002656-phpapp02/85/Lec-38-39-pointers-4-320.jpg)
![Array Accessing Using Pointers
int main()
{
int intarray[5] = { 31, 54, 77, 52, 93 };
for(int j=0; j<5; j++)
cout << *( intarray + j ) << endl;
getch();
return 0;
}](https://image.slidesharecdn.com/lec-38-39-pointers-130222002656-phpapp02/85/Lec-38-39-pointers-5-320.jpg)
![Passing Arrays to Function
const int MAX = 5;
void centimize(double*);
int main()
{ double varray[MAX] = { 10.0, 43.1, 95.9, 59.7, 87.3 };
centimize(varray);
for(int j=0; j<MAX; j++)
cout << varray[j] << endl;
getch(); return 0; }
void centimize(double* ptrd)
{ for(int j=0; j<MAX; j++)
*ptrd++ = *ptrd * 2.54; } //*ptrd++ = *(ptrd++)](https://image.slidesharecdn.com/lec-38-39-pointers-130222002656-phpapp02/85/Lec-38-39-pointers-11-320.jpg)
Lec 38.39 - pointers
- 1. Chapter: 10 Pointers Lecture: 38 and 39 Date: 18.10.2012
- 2. Accessing Addresses int main() { int IntVar1 = 25; int IntVar2 = 11; int* ptr; //pointer to integers ptr = &IntVar1; //pointer points to IntVar1 cout << ptr << endl //print the address of IntVar1 ptr = &IntVar2 cout << ptr << endl //print the address of IntVar2 getch(); return 0; }
- 3. Accessing Contents int main() { int IntVar1 = 25; int IntVar2 = 11; int* ptr; //pointer to integers ptr = &IntVar1; //pointer points to IntVar1 cout << *ptr << endl //print the content of IntVar1 ptr = &IntVar2 cout << *ptr << endl //print the content of IntVar2 getch(); return 0; }
- 4. Array Accessing Using Index int main() { int intarray[5] = { 31, 54, 77, 52, 93 }; for(int j=0; j<5; j++) cout << intarray[j] << endl; getch(); return 0; }
- 5. Array Accessing Using Pointers int main() { int intarray[5] = { 31, 54, 77, 52, 93 }; for(int j=0; j<5; j++) cout << *( intarray + j ) << endl; getch(); return 0; }
- 6. Counting by Integers - Arrays
- 7. Passing Arguments to Functions Arguments can be passed to functions in three different ways: (i) by value, (ii) by reference, and (iii) by pointers A function can change the values in a calling function if the arguments are passed by a reference or by a pointer.
- 8. Pass-by-Reference void centimize(double& ); int main() { double var = 2.5; centimize(var); cout << var << endl; getch(); return 0; } void centimize(double& v) { v = v * 100; }
- 9. Pass-by-Pointer void centimize(double* ); int main() { double var = 2.5; centimize(&var); cout << var << endl; getch(); return 0; } void centimize(double* ptrd) { *ptrd = *ptrd * 100; }
- 10. Pointer Passed to Function
- 11. Passing Arrays to Function const int MAX = 5; void centimize(double*); int main() { double varray[MAX] = { 10.0, 43.1, 95.9, 59.7, 87.3 }; centimize(varray); for(int j=0; j<MAX; j++) cout << varray[j] << endl; getch(); return 0; } void centimize(double* ptrd) { for(int j=0; j<MAX; j++) *ptrd++ = *ptrd * 2.54; } //*ptrd++ = *(ptrd++)
- 12. Pointer Passed to Function
- 13. Assignment # 02 (i) Write a note on sorting with an example. (ii) What is bubble sort? Write a program implementing bubble sort using pointers.
- 14. Assignment # 02 (i) Write a note on sorting with an example (ii) What is bubble sort? Write a program implementing bubble sort using pointers. Viva voce for the first and second assignment is scheduled to be conducted on 24th October.