stack program in c++ code example

Example 1: stack c++

stack<int> stk;
stk.push(5);
int ans = stk.top(5); // ans =5
stk.pop();//removes 5

Example 2: stack c++

/* Stack is a data structure that provides two O(1) time operations:
adding an element to the top and removing an element from the top.
It is only possible to access the top element of a stack. */
stack<int> s;
s.push(3);
s.push(2);
s.push(5);
cout << s.top(); // 5
s.pop();
cout << s.top(); // 2

Example 3: write a program to implement stack using array

#include <iostream>
using namespace std;
int stack[100], n=100, top=-1;
void push(int val) {
   if(top>=n-1)
   cout<<"Stack Overflow"<<endl;
   else {
      top++;
      stack[top]=val;
   }
}
void pop() {
   if(top<=-1)
   cout<<"Stack Underflow"<<endl;
   else {
      cout<<"The popped element is "<< stack[top] <<endl;
      top--;
   }
}
void display() {
   if(top>=0) {
      cout<<"Stack elements are:";
      for(int i=top; i>=0; i--)
      cout<<stack[i]<<" ";
      cout<<endl;
   } else
   cout<<"Stack is empty";
}
int main() {
   int ch, val;
   cout<<"1) Push in stack"<<endl;
   cout<<"2) Pop from stack"<<endl;
   cout<<"3) Display stack"<<endl;
   cout<<"4) Exit"<<endl;
   do {
      cout<<"Enter choice: "<<endl;
      cin>>ch;
      switch(ch) {
         case 1: {
            cout<<"Enter value to be pushed:"<<endl;
            cin>>val;
            push(val);
            break;
         }
         case 2: {
            pop();
            break;
         }
         case 3: {
            display();
            break;
         }
         case 4: {
            cout<<"Exit"<<endl;
            break;
         }
         default: {
            cout<<"Invalid Choice"<<endl;
         }
      }
   }while(ch!=4);
   return 0;
}

Example 4: push pop code in c++

#include<iostream>
using namespace std;
#define Max 100
class stack{
	public:
		int top;
		int size;
		int *s;
		int stack[Max];
		
		void push()
		{
			int value;
			if(top==size-1)
			{
				cout<<"overflow";
			}
			else
			{
				cout<<"Enter value to push \n";
				cin>>value;
				top++;
				stack[top]=value;
			}
		}
		int pop()
		{
			if(top==-1)
			{
				cout<<"Underflow";
			}
			else
			{
				cout<<"Deleted value is \n"<<stack[top];
				top--;
			}
		}
		void display()
		{
			int i;
			for(i=top;i>=0;i--)
			{
				cout<<stack[i]<<endl;
			}
		}
};
int main()
{
	stack st;
	cout<<"Enter the size of the stack";
	cin>>st.size;
	st.s=new int[st.size];
	st.top=-1;
	int ch;
	while(st.size!=0)
	{	
	cout<<endl<<"    #####       STACK MENU     #####     "<<endl;
	cout<<"1. PUSH OPERATION \n2. POP OPERATION \n3. DISPLAY \n4.Exit \n";
	cin>>ch;
	switch(ch)
	{
		case 1: 
		    st.push();
		    break;
		case 2:
			st.pop();
			break;
		case 3:
			st.display();
			break;
		case 4:
			exit(0);
			
		default:cout<<"\n Choose correct option";
	}
}
return 0;
}

Example 5: stack implementation in c

#include <stdio.h>

int MAXSIZE = 8;       
int stack[8];     
int top = -1;            

int isempty() {

   if(top == -1)
      return 1;
   else
      return 0;
}
   
int isfull() {

   if(top == MAXSIZE)
      return 1;
   else
      return 0;
}

int peek() {
   return stack[top];
}

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

int push(int data) {

   if(!isfull()) {
      top = top + 1;   
      stack[top] = data;
   } else {
      printf("Could not insert data, Stack is full.\n");
   }
}

int main() {
   // push items on to the stack 
   push(3);
   push(5);
   push(9);
   push(1);
   push(12);
   push(15);

   printf("Element at top of the stack: %d\n" ,peek());
   printf("Elements: \n");

   // print stack data 
   while(!isempty()) {
      int data = pop();
      printf("%d\n",data);
   }

   printf("Stack full: %s\n" , isfull()?"true":"false");
   printf("Stack empty: %s\n" , isempty()?"true":"false");
   
   return 0;
}