DataBuffer Fixed Buffer Init

#include <iostream>
using namespace std;

// Write your DataBuffer class here
class DataBuffer{
    int size,buffer[20],writeindex;
    public:
        DataBuffer(int s){
            if(s<1)size=1;
            else if(s>20)size=20;
            else size = s;
            buffer[size] = 0;
            writeindex = 0;
        }
        
        void push(int v){
            if(writeindex<size){
                buffer[writeindex++] = v;
            }
        }
        void print(){
            for(int i=0;i<writeindex;i++){
                cout<<buffer[i];
                if(i<(writeindex-1)) cout<<" ";
            }
        }
};

int main() {
    int s, n;
    cin >> s >> n;

    DataBuffer buf(s);

    for (int i = 0; i < n; i++) {
        int x;
        cin >> x;
        buf.push(x);
    }

    buf.print();
    return 0;
}