class Time:
def __init__(self, hour=0, minute=0, second=0):
self.hour = hour
self.minute = minute
self.second = second
def __str__(self):
return "{}:{:02d}:{:02d}".format(self.hour, self.minute, self.second)
def __add__(self, other_time):
new_time = Time()
if (self.second + other_time.second) >= 60:
self.minute += 1
new_time.second = (self.second + other_time.second) - 60
else:
new_time.second = self.second + other_time.second
if (self.minute + other_time.minute) >= 60:
self.hour += 1
new_time.minute = (self.minute + other_time.minute) - 60
else:
new_time.minute = self.minute + other_time.minute
if (self.hour + other_time.hour) > 24:
new_time.hour = (self.hour + other_time.hour) - 24
else:
new_time.hour = self.hour + other_time.hour
return new_time
def __sub__(self, other_time):
new_time = Time()
if (self.second + other_time.second) >= 60:
self.minute += 1
new_time.second = (self.second + other_time.second) - 60
else:
new_time.second = self.second + other_time.second
if (self.minute + other_time.minute) >= 60:
self.hour += 1
new_time.minute = (self.minute + other_time.minute) - 60
else:
new_time.minute = self.minute + other_time.minute
if (self.hour + other_time.hour) > 24:
new_time.hour = (self.hour + other_time.hour) - 24
else:
new_time.hour = self.hour + other_time.hour
return new_time
def main():
time1 = Time(1, 20, 10)
print(time1)
time2 = Time(24, 41, 30)
print(time1 + time2)
print(time1 - time2)
main()
In the class Time, I have defined methods add and sub with the same function(basically they are the same methods with a different call). when I run print(time1 + time2), print(time1 -time2) I expect to get the same output. But Instead, I end up getting the following output.
Output:
1:20:10
2:01:40
3:01:40
expected Output:
1:20:10
2:01:40
2:01:40
I would be glad if someone can point out a way to interpret the above code with respect to the output it generates, or explain what is actually happening when I run the above code that is leading to the output generated.
The lines self.minute += 1 and self.hour += 1 mean that your __add__ and __sub__ both modify the left-hand argument to +/-. Thus, after evaluating time1 + time2, the value of time1 will be different, so you'll get a different answer when you then evaluate time1 - time2.