155

class MinStack {
public:

stack<int>st;
vector<int>mm;
int n=0,m=0;
    MinStack() {
        
    }
    
    void push(int val) {
        st.push(val);
        if(n!=0){
            val=min(val,mm[n-1]);
        }
        if(m==n){
            mm.push_back(val);
            m+=1;
        }else
            mm[n]=val;
        n+=1;
    }
    
    void pop() {
        st.pop();
        n--;
    }
    
    int top() {
        return st.top();
        
    }
    
    int getMin() {
        return mm[n-1];
    }
};

/**
 * Your MinStack object will be instantiated and called as such:
 * MinStack* obj = new MinStack();
 * obj->push(val);
 * obj->pop();
 * int param_3 = obj->top();
 * int param_4 = obj->getMin();
 */