1.000: C0 arrived [ ]
1.000: C0 service begin (by S0)
1.200: C1 arrived [ ]
1.200: C1 service begin (by S1)
1.400: C2 arrived [ ]
1.400: C2 joined queue [ ]
1.600: C3 arrived [ C2 ]
1.600: C3 joined queue [ C2 ]
2.000: C0 service done (by S0)
2.000: C0 departed
2.000: C2 service begin (by S0)
2.100: C4 arrived [ C3 ]
2.100: C4 joined queue [ C3 ]
2.200: C1 service done (by S1)
2.200: C1 departed
2.200: C3 service begin (by S1)
3.000: C2 service done (by S0)
3.000: C2 departed
3.000: C4 service begin (by S0)
3.200: C3 service done (by S1)
3.200: C3 departed
4.000: C4 service done (by S0)
4.000: C4 departed