Array implementation of Stack

Here we see how to implement the stack using C array data type:


#include <stdio.h>
#define MAX 5 //maximum size of stack

int top = -1; //top of stack
int stack[MAX]; // stack

int pop();
void push(int);
void display(); // for displaying stack elements

int main(){
 push(1); 
 push(3);
 push(5); display();
 pop(); 
 pop(); display();
 pop(); 
 pop();
 return 0;
}

void push(int item){
 if(top == MAX-1){ //check for overflow
  printf("Stack overflow\n");
 }
 else{
  stack[++top] = item;
  printf("Pushed item = %d\n", item);
 }
}

int pop(){
 if(top == -1){ // check for underflow
  printf("Stack underflow\n");
 }
 else{
  return stack[top--];
 }
}

void display(){
 printf("The stack elements are: ");
 for( int i = 0; i <= top; i++){
  printf("%d ", stack[i]);
 }
 printf("\n");
}

Output:


Pushed item = 1
Pushed item = 3
Pushed item = 5
The stack elements are: 1 3 5
The stack elements are: 1
Stack underflow

Comments

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