public void relateUsers(int uid1, int uid2){
		try {

			rStat.acquire();
			if(userRelations[memberIdxs.get(uid1)] != null){
				HashMap<Integer, String> rels = userRelations[memberIdxs.get(uid1)];
				if(!rels.containsKey(uid2)){
					rels.put(uid2,"");
				}
				userRelations[memberIdxs.get(uid1)]= rels;
			}else{
				HashMap<Integer, String> rels = new HashMap<Integer, String>();
				rels.put(uid2,"");
				userRelations[memberIdxs.get(uid1)]= rels;
			}
			
			if(userRelations[memberIdxs.get(uid2)] != null){
				HashMap<Integer, String> rels = userRelations[memberIdxs.get(uid2)];
				if(!rels.containsKey(uid1)){
					rels.put(uid1,"");
				}
				userRelations[memberIdxs.get(uid2)]= rels;
			}else{
				HashMap<Integer, String> rels = new HashMap<Integer, String>();
				rels.put(uid1,"");
				userRelations[memberIdxs.get(uid2)]= rels;	
			}

			rStat.release();
		} catch (Exception e) {
			System.out.println("Error in Rels");
			e.printStackTrace(System.out);
			System.exit(-1);
		}		
	}