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L13 Problem 7
Raw
gistfile1.txt
"""
This code will produce "The output of random.randint(1, 10) after a specific seed is shown below."
"""
import random
random.seed(9001)
print random.randint(1, 10)
print random.randint(1, 10)
print random.randint(1, 10)
print random.randint(1, 10)
print random.randint(1, 10)
"""Output
1
3
6
6
7
"""
"""
Explanation: @asterism (Adaptation)
a) All of the problems (below) use random.randint(1, 10), just like above.
b) They also use the same seed, 9001 - random.seed(9001) - just like above.
c) Therefore, when you see random.seed(9001) and random.randint(1, 10) (below) you know
it will return the SAME numbers as above, in the SAME sequence:
1, 3, 6, 6, 7.
"""
random.seed(9001)
for i in xrange(random.randint(1, 10)):
print random.randint(1, 10)
"""
Explanation: @Alfredo42 (Adaptation)
a) The for loop calls random.randint for the 1st time.
a.i) Which sets the for loop to read: for i in xrange(1) (the 1st number in the "pre-est. random sequence" = 1, 3, 6, 6, 7).
a.ii) Which sets the for loop to run: 1 time.
b) The print statement, calls random.randint for a 2nd time.
b.i) Therefore, the print statement prints the 2nd number in the sequence, which is: 3.
c) Notes:
c.i) I would like to understand why we used xrange here and not range?
c.ii) Is my a.i) explanation accurate? Could it be improved?
"""
random.seed(9001)
d = random.randint(1, 10)
for i in xrange(random.randint(1, 10)):
print d
"""
Explanation: @Alfredo42 (Adaptation)
a) The "d =" statement calls random.randint for the 1st time.
a.i) Which sets d to be the 1st number in the sequence, which is: 1.
b) The for loop calls random.randint for the 2nd time.
b.i) Which sets the for loop to read: for i in xrange(3) (the 2nd number in the "pre-est. random sequence" = 1, 3, 6, 6, 7).
b.ii) Which sets the for loop to run: 3 times.
c) The print statement, calls "print d", which = 1.
c.i) Given the for loop runs 3 times (see b.ii), 1 is printed 3 times.
"""
random.seed(9001)
d = random.randint(1, 10)
for i in xrange(random.randint(1, 10)):
if random.randint(1, 10) < 7:
print d
else:
random.seed(9001)
d = random.randint(1, 10)
print random.randint(1, 10)
"""
Explanation: @Alfredo42 (Adaptation)
a) The "d =" statement calls random.randint for the 1st time.
a.i) Which sets d to be the 1st number in the sequence, which is: 1.
b) The for loop calls random.randint for the 2nd time.
b.i) Which sets the for loop to read: for i in xrange(3) (the 2nd number in the "pre-est. random sequence" = 1, 3, 6, 6, 7).
b.ii) Which sets the for loop to run: 3 times.
c) 1st run of if statement: The if statement calls random.randint for the 3rd time.
c.i) Which sets "random.randint(1, 10)" = 6.
c.ii) As 6 is < 7, it prints d, which = 1.
d) 2nd run of if statement: The if statement calls random.randint for the 4th time.
d.i) Which sets "random.randint(1, 10)" = 6.
d.ii) As 6 is < 7, it prints d, which = 1.
e) 3rd run of if statement: The if statement calls random.randint for the 5th time.
e.i) Which sets "random.randint(1, 10)" = 7.
e.ii) As 7 is NOT < 7, it goes to the else statement, which calls on random.randint 2 times...
e.iii) Which therefore prints the 2nd number in the "pre-est. random sequence = 3.
"""
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