typedef struct CHAP CHAP;

struct CHAP{

 int ID;
 CHAP** list;
 int nb;

};

CHAP* find_chap(CHAP* ch, CHAP* target){

     if (ch->ID == target->ID) return ch;

     for (int i=0; i<ch->nb; i++){
         find_chap(ch->list[i], target);
     }
    //return NULL?
 }