Reverse Stack Using Recursion

For this particular code we are going to get deeper into recursive techniques. Here we will be simply reversing the order of a stack to print elements in reverse.

Original Stack->                                             Reverse Stack
        1   --top                                                            4   --top
        2                                                                       3
        3                                                                       2
        4                                                                       1

Full code->

#include<bits/stdc++.h>
unsing namespace std;

stack<char> s;
string n;

char insert_at_bottom(char x)
{
    if(s.size()==0)
        s.push(x);
    else
        char a = s.top();
        s.pop();
        insert_at_bottom(x);
        
        s.push(a);
}

char reverse()
{
    if(s.size()>0)
        char x= s.top();
        s.pop();
        reverse();
        insert_at_bottom(x);
}

int main()
{
        s.push(1); s.push(2); s.push(3); s.push(4);
        reverse();
        
        while(!s.empty())        //store reverse values in a string 
            char p= s.top();
            s.pop();
            n+=p;

    cout<<n[3]<<n[2]<<n[1]<<n[0];
    return 0;
}

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