Identificando estructuras en assembly

#include <stdint.h>
#include <stdlib.h>


struct Node {
    int data;
    Node *left;
    Node *right;
};

int lessThan(int a, int b) { return a < b; };

int find(Node *r, int (*f)(int,int), int k) {
    while(r) {

        if (f(k,r->data)) r = r->left;
        else if (f(r->data,k)) r=r->right;
        else return 1;        
    }
    return 0;
}