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C++ Stack Exercises: Reverse a stack (using a vector) elements

C++ Stack: Exercise-26 with Solution

Write a C++ program that reverses the stack (using a vector) elements.

Test Data:
Create a stack object:
Input and store (using vector) some elements onto the stack:
Stack elements are: 1 3 2 6 5 -1 0
Reverse the elements of the said stack:
Stack elements are: 0 -1 5 6 2 3 1

Sample Solution:

C++ Code:

#include <iostream>
#include <vector>
#include<algorithm>

using namespace std;

class Stack {
private:
    vector<int> elements; // Vector to store elements

public:
    void push(int element) {
        elements.push_back(element); // Add element to the end of the vector
    }

    void pop() {
        if (elements.empty()) {
            cout << "Stack is full" << endl; // Display full message if the stack is empty
        } else {
            elements.pop_back(); // Remove the last element from the vector
        }
    }

    int top() {
        if (elements.empty()) {
            cout << "Stack is empty" << endl; // Display empty message if the stack is empty
            return 0;
        } else {
            return elements.back(); // Return the last element in the vector
        }
    }

    bool empty() {
        return elements.empty(); // Check if the vector is empty
    }

    void display() {
        vector<int> v = elements;
        if (v.empty()) {
            cout << "Stack is empty" << endl; // Display empty message if the stack is empty
            return;
        }
        cout << "Stack elements are: ";
        for (int i = 0; i < v.size(); i++) {
            cout << v[i] << " "; // Display the elements of the stack
        }
        cout << endl;
    }

    // Function to reverse the elements of the stack
    void reverse_stack() {
        int n = elements.size();
        for (int i = 0; i < n / 2; i++) {
            int temp = elements[i];
            elements[i] = elements[n - i - 1];
            elements[n - i - 1] = temp;
        }
    }
};  

int main() {
    Stack stack;
    cout << "Create a stack object:\n"; // Initialize a stack
    cout << "\nInput and store (using vector) some elements onto the stack:\n";
    stack.push(1);
    stack.push(3);
    stack.push(2);
    stack.push(6);
    stack.push(5);
    stack.push(-1);
    stack.push(0);
    stack.display();
    cout << "\nReverse the elements of the said stack:\n";
    stack.reverse_stack();
    stack.display();
    cout << "\nRemove two elements from the stack:\n";
    stack.pop();
    stack.pop();
    stack.display();
    cout << "\nInput three elements onto the stack:\n";
    stack.push(4);
    stack.push(7);
    stack.push(-2);
    stack.display();
    cout << "\nReverse the elements of the said stack:\n";
    stack.reverse_stack();
    stack.display();
    return 0;
}

Sample Output:

Create a stack object:

Input and store (using vector) some elements onto the stack:
Stack elements are: 1 3 2 6 5 -1 0 

Reverse the elements of the said stack:
Stack elements are: 0 -1 5 6 2 3 1 

Remove two elements from the stack:
Stack elements are: 0 -1 5 6 2 

Input three elements onto the stack:
Stack elements are: 0 -1 5 6 2 4 7 -2 

Reverse the elements of the said stack:
Stack elements are: -2 7 4 2 6 5 -1 0 

Flowchart:

Flowchart: Reverse a stack (using a vector) elements.
Flowchart: Reverse a stack (using a vector) elements.
Flowchart: Reverse a stack (using a vector) elements.

CPP Code Editor:

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Previous C++ Exercise: Sort the stack (using a vector) elements.
Next C++ Exercise: Find the middle element(s) of a stack (using a vector).

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