Veri Yapıları

1. Chapter 5
Data Structures
Assoc. Prof. Dr. Oğuz FINDIK
2016-2017
KBUZEM
KARABUK UNIVERSITY
1

2.  A stack is an abstract data type, commonly used in most
programming languages.
 Like real world applications, stack allows all data operations
at one end only. At any given time, we can only Access the
top element of a stack.
 This feature makes it LIFO data structure. LIFO stands for
Last-in-first-out. Here the element which is placed last, is
accessed first. In stack terminology, insertion operation is
called PUSH operation and removal operation is called POP
operation.
2
Stacks

3. push() – pushing an element into the stack
pop() – get an element from stack and remove it ,
peek() – get the element from top of the stack, without
removing it.
isFull()- check stack whether is full or not.
isEmpty() - check stack whether is empty or not.
3
Basic Operations

4. int peek() {
return stack[top];
}
bool isfull() {
if(top == MAXSIZE)
return true;
else
return false;
}
4
peek,isFull and isEmpty function
bool isempty() {
if(top == -1)
return true;
else
return false;
}

5.  The process of putting a new data element onto stack is known
as PUSH operation. Push operation invoşves series of steps –
 Step 1 − Check if stack is full.
 Step 2 − If stack is full, produce error and exit.
 Step 3 − If stack is not full, increment top to point next empty
space.
 Step 4 − Add data element to the stack location, where top is
pointing.
 Step 5 − return success.
5
PUSH operation

6. 6
Push operation
void push(int data) {
if(!isFull()) {
top = top + 1;
stack[top] = data;
}else {
printf("Could not
insert data, Stack is
full.n");
}
}

7. A POP operation may involve the following steps −
Step 1 − Check if stack is empty.
Step 2 − If stack is empty, produce error and exit.
Step 3 − If stack is not empty, access the data element at which top is
pointing.
Step 4 − Decrease the value of top by 1.
Step 5 − return success
7
POP operation

8. 8
POP operations
int pop(int data) {
if(!isempty()) {
data = stack[top];
top = top - 1;
return data;
}else {
printf("Could not retrieve
data, Stack is empty.n");
}
}

9. 9
Example
bool isEmpty() {
extern indis;
bool temp = true;
if (indis == - 1)
temp = true;
else
temp = false;
return temp;}
int push(char c, char *s) {
extern indis;
if (!isFull(indis)) {
indis++;
*(s + indis) = c;
return 1;
} else
return 0;}
* myfunctions.c
#include "myheaderfile.h"
int strl_ln(char *s1) {
int length = 0;
while (s1 != '0') {
length++;
s1++;
}
return length++;}
bool isFull() {
extern indis;
bool temp = true;
if (indis == STACKSIZE-1)
temp = true;
else
temp = false;
return temp;}

10. 10
Example
char pop(char *s) {
extern indis;
if (!isEmpty(indis))
return s[indis--];
}
char peek(char *s) {
extern indis;
if (!isEmpty(indis))
return s[indis];
}

11. 11
Example (MYHEADERFILE.h)
#ifndef MYHEADERFILE_H_
#define MYHEADERFILE_H_
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define STACKSIZE 10
#define N 10
typedef enum
bool{true=1,false=0}bool;
int str_ln(char *);
int push(char c,char*);
char pop(char*);
char peek(char*);
bool isFull();
bool isEmpty();
#endif /* MYHEADERFILE_H_ */

12. 12
Example (Ders.c)
#include "myheaderfile.h"
int indis=-1;
char stack[STACKSIZE];
int main(void) {
push('s',stack);push('a',stack);pu
sh('f',stack);
push('r',stack);push('a',stack);pu
sh('n',stack);
push('b',stack);push('o',stack);
push('l',stack);push('u',stack);pu
sh('u',stack);
int i =0;
for(i=0;i<STACKSIZE;i++){
printf("%c",pop(stack));
}
return EXIT_SUCCESS;
}

13. 13
Example 2
int genericPush(void *c, int
boyut) {
extern indis,stack;
if (!isFull(indis)) {
indis++;
memcpy(stack, c, boyut);
stack = stack + boyut;
return 1;
} else
return 0;
}
void *genericPop( int boyut) {
extern indis,stack;
if (!isEmpty(indis)) {
indis--;
stack = stack - boyut;
return stack;
}
}

14. 14
Example 2
#include "myheaderfile.h"
void *stack;
int indis = -1;
typedef double myType;
#define N 10
int main(void) {
stack = calloc(N, sizeof(void *));
myType s[] = { 65.0, 66.2, 67.4, 68.3,
69, 70, 71.3,72.5,73.4,74.5 };
char *p = calloc(N, sizeof(void *));
int i;
myType value;
int lengthOfVariable = sizeof(myType);
printf("length Of Variable:%dn",
lengthOfVariable);
for (i = 0; i < N; i++) {
value = s[i];
if (!genericPush(&value,
lengthOfVariable)) {
printf("stack doldu ");
}
}
for (i = 0; i < N; i++) {
printf("%7.2f", *(myType*)
genericPop(lengthOfVariable));
}
return EXIT_SUCCESS;
}