The second tier is called precondition matching, filtering out the services that don't satisfy the precondition.

第二层是前提匹配，淘汰不满足服务前提的服务；

youdao

The second tier is called precondition matching, filtering out the services that don't satisfy the precondition.

第二层是前提匹配，淘汰不满足服务前提的服务；

youdao