Post by Chunxi Zhang
Chunxi's CodingBat2
Choose three exercise.
1.String2-xyz_there
This question did take me some time. I thought several different ways to express my idea. But I do not know a method which can Then I change my thoughts. It could be 2 circumstances. If the 'xyz' is str[0:3], no matter where the '.' is, it will return True. And if there are '.xyz', it will return false. I can use != to except the '.'.
def xyz_there(str):
for i in range(len(str)):
if str[i] != '.' and str[i+1:i+4] == 'xyz':
return True
if str[0:3] == 'xyz':
return True
return False
2.Logic2-make_bricks
I am impressed with this question is because it took me some time to understand the request. After watching the vedio to understand what brick means, I begin to code. The code isself is not hard. But it is problematic to know what exactly I want.
def make_bricks(small, big, goal):
if goal % 5 >= 0 and goal % 5 - small <= 0 and small + 5*big >= goal:
return True
else:
return False
3.Logic2-long_sum
This question is strightforward. But I spent more time on debugging. The original code of mine is
def lone_sum(a, b, c):
if a == b:
return c
if a == c:
return b
if b == c:
return a
if a == b == c:
return 0
else:
return a+b+c
However, it cannot pass the test. At first, I did not what is wrong. Then I read the test carefully and I found out all the problem happened when a=b=c. So I noticed that the problem is about the order. a = b= c should be ordered first.
def lone_sum(a, b, c):
if a == b == c:
return 0
if a == b:
return c
if a == c:
return b
if b == c:
return a
else:
return a+b+c
Pictures
warmup2
string2
list2
logic2
