+ FatTreeNode *source, *destination, *currentNode;
+ std::vector<NetworkLink*> route;
+ source = this->nodes.find(src->getId())->second;
+ destination = this->nodes.find(dst->getId())->second;
+
+ int d, k; // as in d-mod-k
+
+ currentNode = source;
+
+ // up part
+ while (!isInSubTree(currentNode, destination)) {
+ d = destination->position;
+
+ for (unsigned int i = 0 ; i < currentNode->level ; i++) {
+ d /= this->upperLevelNodesNumber[i];
+ }
+ k = this->upperLevelNodesNumber[currentNode->level] *
+ this->lowerLevelNodesNumber[currentNode->level];
+ d = d % k;
+ route.push_back(currentNode->parents[d]->upLink);
+ currentNode = currentNode->parents[d]->upNode;
+ }