sortare insertie cu liste

#include <iostream>

using namespace std;

struct nod
{
    int h;
    nod* leg;
};

int main()
{
    int n, a, i;
    nod* prim, *p, *q, *r;
    cout<<"Nr de elevi: ";
    cin>>n;
    prim=new nod;
    prim->h=INT_MAX;
    prim->leg=NULL;
    for(int i=1; i<=n; i++)
    {
        cout<<"Introduceti inaltimea: "; cin>>a;
        q=new nod;
        q->h=a;
        if(a<prim->h)
        {
            q->leg=prim;
            prim=q;
        }
        else{
        p=prim;
        while(a>=(p->h))
        {
            r=p;
            p=p->leg;
        }
        q->leg=p;
        r->leg=q;
        }
    }
    cout<<"Sirul sortat este: ";
    p=prim;
    for(i=1; i<=n; i++)
    {
        cout<<p->h<<" ";
        p=p->leg;
    }
    return 0;
}