double RPNStackCalc(stack stk)
{
int i;
node item;
stack calc;
memset(&calc,0,sizeof(calc));
calc.size=0;
for(i=0;i<stk.size;i++)
{
item=stk.item[i];
if(item.is_num)
{
push(&calc,item);
}else{
node a,b;
nodecpy(&b,pop(&calc));
nodecpy(&a,pop(&calc));
item.data.num=calc2(a.data.num,b.data.num,item.data.op);
item.is_num=true;
push(&calc,item);
}
}
if(calc.size!=1||isEmpty(calc))
return -1;
else
return (calc.item[0].data.num);
}
fstree_node_t treecpy ( fstree_node_t old_node ) {
fslist_node_t aux_node;
fstree_node_t new_node;
if (!old_node->children->size)
return nodecpy(old_node);
new_node = nodecpy(old_node);
aux_node = old_node->children->first;
while (aux_node != NULL) {
add_child(new_node, treecpy(aux_node->child));
aux_node = aux_node->next;
}
return new_node;
}
