From Lanzhou to Jiuzhaigou: take train to Chengdu and then take bus to Jiuzhaigou. CNY73-416,bus fare CNY63-90.
From Jiuzhaigou to Huanglong, take bus, Bus fare around CNY50
From Huanglong to Chengdu, take bus, the bus trip is very uncomfortable.
Or you can take a train or flight to Chengdu or xian first, then flight to Jiuzhaigou.