DataBuffer Fixed Buffer Init

#include <iostream>
using namespace std;

// Write your DataBuffer class here
class DataBuffer{
    int size;
    int buffer[20];
    int writeIndex;

    public:
    DataBuffer(int s) noexcept
    {
        if ( s < 1) size = 1;
        else if ( s > 20 ) size = 20;
        else size = s;
        
        for (int i = 0; i < 20; i++) buffer[i] = 0;

        writeIndex = 0;
    }

    void push(int v) noexcept
    {
        if ( writeIndex < size) buffer[writeIndex++] = v;
    }

    void print() const noexcept
    {
        for (int i = 0; i < writeIndex; i++) cout << buffer[i] << " " ;
    }
};
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;
}

Solving Approach