[C++]Arbori binari

#include <iostream>

using namespace std;

int d[100], s[100], n, x;
void citire()
{
    int i;
    for(int i=1; i<=n; i++)
    {
        cout<<"Dati fiul stang al nodului "<<i<<": "; cin>>s[i];
        cout<<"Dati fiul drept al nodului "<<i<<": "; cin>>d[i];
    }
}

void srd(int x)
{
    if(s[x] != 0) srd(s[x]);
    cout<<x<<" ";
    if(d[x] != 0) srd(d[x]);
}
void rsd(int x)
{
    cout<<x<<" ";
    if(s[x] != 0) srd(s[x]);
    if(d[x] != 0) rsd(d[x]);
}
void sdr(int x)
{
    if(s[x] != 0) sdr(s[x]);
    if(d[x] != 0) sdr(d[x]);
    cout<<x<<" ";
}
int main()
{
    cout<<"Nodul radacina: "; cin>>x;
    cout<<"Numarul de noduri: "; cin>>n;
    citire();
    cout<<'\n';
    srd(x); cout<<'\n';
    rsd(x); cout<<'\n';
    sdr(x); cout<<'\n';
    return 0;
}