#include <iostream>
using namespace std;
//implemenation of stacks using arrays.
#define Max 20
class Stack{
int stack[Max];
int top = 0;
public:
void push(int value)
{
if(top == Max-1)
{
cout<<"Stack Overflow"<<"\n";
return;
}
top++;
stack[top] = value;
}
int pop()
{
if(top == 0)
{
cout<<"Underflow"<<"\n";
return -1;
}
int value = stack[top];
top--;
return value;
}
int peek()
{
return stack[top];
}
};
int main() {
Stack s1;
s1.push(5);
s1.push(6);
s1.push(7);
cout<<s1.pop()<<"\n";
cout<<s1.peek()<<"\n";
return 0;
}
