In console of PC1,
pc1# show ip
pc1# ip 4.4.4.2/24 4.4.4.1
pc1# save
In console of PC2,
pc1# show ip
pc1# ip 5.5.5.2/24 5.5.5.1
pc1# save
In console of r1,
r1# conf t
(config)r1# int f1/1
(config-if)r1# no switchport
(config-if)r1# ip addr 4.4.4.1 255.255.255.0
(config-if)r1# do wr
(config-if)r1# exit
(config)r1# int f1/2
(config-if)r1# no switchport
(config-if)r1# ip addr 5.5.5.1 255.255.255.0
(config-if)r1# do wr
