structures de contrôle en python - cpge-paradise.com

Structures de controle en Python

G. Dewaele

4 septembre 2017

Lycee Louis-le-Grand

Structure conditionnelle

expr_bool

True

False

instruction_1

instruction_n

if expr_bool :

instruction_1...

instruction_n...

2

Exemple

if x%2==0 :print("Pair")

10

23x

x%2==0?x%2==0?

True

False

Print("Pair")

3

Exemple

if x%2==0 :print("Pair")

10

23x

x%2==0?x 2==0?x%2==0?

True

False

Print("Pair")

3

Exemple

if x%2==0 :print("Pair")

10

23x

x%2==0?x%2==0?

True

False

Print("Pair")Print("Pair")

3

Exemple

if x%2==0 :print("Pair")

10

23x

x%2==0?x%2==0?

True

False

Print("Pair")

3

Exemple

if x%2==0 :print("Pair")

10

23x

x%2==0?x%2==0?

True

False

Print("Pair")

3

Exemple

if x%2==0 :print("Pair")

10

23x

x%2==0?x 2==0?x%2==0?

True

False

Print("Pair")

3

Exemple

if x%2==0 :print("Pair")

10

23x

x%2==0?x%2==0?

True

False

Print("Pair")

3

Structure conditionelle (2)

expr_bool

True

False

instruction_A_1

instruction_A_n

instruction_B_1

instruction_B_n

if expr_bool :

instruction_A_1...

instruction_A_n

else :instruction_B_1...

instruction_B_n...

4

Exemple

if x%2==0 :print("Pair")

else :print("Imp.")

10

23x

x%2==0?x%2==0?

True

False

Print("Pair") Print("Imp.")

5

Exemple

if x%2==0 :print("Pair")

else :print("Imp.")

10

23x

x%2==0?x 2==0?x%2==0?

True

False

Print("Pair") Print("Imp.")

5

Exemple

if x%2==0 :print("Pair")

else :print("Imp.")

10

23x

x%2==0?x%2==0?

True

False

Print("Pair")Print("Pair") Print("Imp.")

5

Exemple

if x%2==0 :print("Pair")

else :print("Imp.")

10

23x

x%2==0?x%2==0?

True

False

Print("Pair") Print("Imp.")

5

Exemple

if x%2==0 :print("Pair")

else :print("Imp.")

10

23x

x%2==0?x%2==0?

True

False

Print("Pair") Print("Imp.")

5

Exemple

if x%2==0 :print("Pair")

else :print("Imp.")

10

23x

x%2==0?x 2==0?x%2==0?

True

False

Print("Pair") Print("Imp.")

5

Exemple

if x%2==0 :print("Pair")

else :print("Imp.")

10

23x

x%2==0?x%2==0?

True

False

Print("Pair") Print("Imp.")Print("Imp.")

5

Exemple

if x%2==0 :print("Pair")

else :print("Imp.")

10

23x

x%2==0?x%2==0?

True

False

Print("Pair") Print("Imp.")

5

Multiples chemins avec « elif »

if x==0 :print("Nul")

elif x>=0 :print("Pos.")

else :print("Nég.")

x==0? x>=0?

True True

False False

Print("Nul") Print("Pos.") Print("Nég.")

6

Structure « while »

expr_bool

True

False

instruction_1

instruction_n

while expr_bool :

instruction_1...

instruction_n...

7

Exemple

u<5?

True

False

print(u)

u = 2*u

while u<5 :print(u)

u = 2*u

1u

8

Exemple

u<5?u<5?

True

False

print(u)

u = 2*u

while u<5 :print(u)

u = 2*u

1u

8

Exemple

u<5?

True

False

print(u)print(u)

u = 2*u

while u<5 :print(u)

u = 2*u

1u

8

Exemple

u<5?

True

False

print(u)

u = 2*uu = 2*u

while u<5 :print(u)

u = 2*u

1u

8

Exemple

u<5?u<5?

True

False

print(u)

u = 2*u

while u<5 :print(u)

u = 2*u

1

2u

8

Exemple

u<5?

True

False

print(u)print(u)

u = 2*u

while u<5 :print(u)

u = 2*u

1

2u

8

Exemple

u<5?

True

False

print(u)

u = 2*uu = 2*u

while u<5 :print(u)

u = 2*u

1

2u

8

Exemple

u<5?u<5?

True

False

print(u)

u = 2*u

while u<5 :print(u)

u = 2*u

1

2

4

u

8

Exemple

u<5?

True

False

print(u)print(u)

u = 2*u

while u<5 :print(u)

u = 2*u

1

2

4

u

8

Exemple

u<5?

True

False

print(u)

u = 2*uu = 2*u

while u<5 :print(u)

u = 2*u

1

2

4

u

8

Exemple

u<5?u<5?

True

False

print(u)

u = 2*u

while u<5 :print(u)

u = 2*u

1

2

4

8

u

8

Exemple

u<5?

True

False

print(u)

u = 2*u

while u<5 :print(u)

u = 2*u

1

2

4

8

u

8

Calcul du PGCD avec l’algorithme d’Euclide

b>0?

True

False

a,b = b,a%ba,b = b,a%b print(a)

while b>0 :a,b = b,a%b

print(a)

420

126a

b

9

Calcul du PGCD avec l’algorithme d’Euclide

b>0?b>0?

True

False

a,b = b,a%ba,b = b,a%b print(a)

while b>0 :a,b = b,a%b

print(a)

420

126a

b

9

Calcul du PGCD avec l’algorithme d’Euclide

b>0?

True

False

a,b = b,a%ba,b = b,a ba,b = b,a%b print(a)

while b>0 :a,b = b,a%b

print(a)

420

126a

b

9

Calcul du PGCD avec l’algorithme d’Euclide

b>0?b>0?

True

False

a,b = b,a%ba,b = b,a%b print(a)

while b>0 :a,b = b,a%b

print(a)

420

126

42

a

b

9

Calcul du PGCD avec l’algorithme d’Euclide

b>0?

True

False

a,b = b,a%ba,b = b,a ba,b = b,a%b print(a)

while b>0 :a,b = b,a%b

print(a)

420

126

42

a

b

9

Calcul du PGCD avec l’algorithme d’Euclide

b>0?b>0?

True

False

a,b = b,a%ba,b = b,a%b print(a)

while b>0 :a,b = b,a%b

print(a)

420

126

42

0

a

b

9

Calcul du PGCD avec l’algorithme d’Euclide

b>0?

True

False

a,b = b,a%ba,b = b,a%b print(a)print(a)

while b>0 :a,b = b,a%b

print(a)

420

126

42

0

a

b

9

Calcul du PGCD avec l’algorithme d’Euclide

b>0?

True

False

a,b = b,a%ba,b = b,a%b print(a)

while b>0 :a,b = b,a%b

print(a)

420

126

42

0

a

b

9