special task

#include<iostream>
#include<stack>
using namespace std;
void push(int a);
bool isFull(int n);
bool isEmpty();
int pop();
int getMin();
//This is the STL stack (http://quiz.geeksforgeeks.org/stack-container-adaptors-the-c-standard-template-library-stl/).
stack<int> s;
int main(){
    int t;
    cin>>t;
    while(t--){
        int n,a;
        cin>>n;
        while(!isEmpty()){
            pop();
        }
        while(!isFull(n)){
            cin>>a;
            push(a);
        }
        cout<<getMin()<<endl;
    }
}// } Driver Code Ends


/*Complete the function(s) below*/
void push(int a)
{
     //add code here.
     s.push(a);
}

bool isFull(int n)
{
     //add code here.
     if(s.size()==n)
     return 1;
     else return 0;
}

bool isEmpty()
{
    //add code here.
    if(s.empty()) return 1;
    else return 0;
}

int pop()
{
    //add code here.
    s.pop();
}

int getMin()
{
   //add code here.
   int a=s.top();
   while(!s.empty()){
   int b=s.top();
     a=min(a,b);
   s.pop();}
   return a;
}