Below is a summary of all the pit stops made at the Canadian
Grand Prix and the tyres changed. The soft tyre was the prime 
in Canada and the super soft tyre was the option. But the wet
and intermediate tyres were also used due to the weather.

Button:      WN IN (8)  DT (13) WN (19) WN IU (35) IN (37) SSU (51)
Vettel:      WN WN (20) WU IN  (37) SSU (53)  3
Webber:      WN WN (20) WU IN  (36) SSU (50)  3
Schumacher:  WU IU (18) WU (21) WU  IN  (34)  SSN (52) 4
Petrov:      WN WN IN  (36) SSU (53) 2
Massa:       WN WN (21) WU IN  (36) SSU (53)  SSU (54) 4
Kobayashi:   WN WN IN  (36) SSU (53) 2
Alguersuari: WN WN (19) WN IN  (35) SSN (51)  3
Barrichello: WN IN (15) WN (19) WU  IN  (34)  SSN (50) 4
Buemi:       WU IN (17) WN (20) WN  IN  (34)  SSU (50) 4
Rosberg:     WN IU (17) WU (19) WN  IN  (36)  SSN (53) 4
De La Rosa:  WN WN IN  (35) SSU (52) 2
Liuzzi:      WN WN (9)  WU IN  (35) SSN (52)  3
D’Ambrosio:  WN IN (17) WN (23) WN  IN  (33)  DT (36) SSN (52) 5
Glock:       WN WN IN  (34) SSN (51) 2
Trulli:      WN WN (19) WU IN  (36) SSN (52)  SSU (55) 4
Karthikeyan: WN WN IN  (37) SSN (51) 2
Di Resta:    WN WN IN  (35) IN  (43)IN (50) SSN (53) 4
Maldonado:   WN IN (17) WN (19) WU  IU  (35)  SSN (51) SSU (61)5 NC
Heidfeld:    WN WU IN  (35) SSU (52) 2    NC
Sutil:       WN IN (16) WN IN  (34) DT  (45)  IN (49) 4 NC
Alonso:      WN IN (17) WN (19) WU  IN  (36)  3 NC
Kovalainen:  WN WN (19) WU 1    NC
Hamilton:    WN 0  NC

The first column denotes the tyres the driver started the race on.
S = Soft compound
SS = Super Soft compound
W = Wet tyre
I = Intermediate tyre
N = New compound
U = Used compound
DT = Drive through
NC = Not classified
The last column gives the total amount of pit stops.
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