36 lines
679 B
Python
36 lines
679 B
Python
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import math
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num = 1534236469
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def reverse(num):
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# handle negative case
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neg = False
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if num<0:
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neg = True
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num = abs(num)
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rev = 0
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while num>0:
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# pop last digit
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popped = num % 10
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num = math.floor(num / 10)
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# handle overflow
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if (rev > 2**31 / 10) or (rev == 2**31 / 10 and popped>7): return 0
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if (rev < -2**31 / 10) or (rev == -2**31 / 10 and popped<-8): return 0
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rev = rev * 10 + popped
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print(num, popped, rev)
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return rev*-1 if neg else rev
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print( reverse(num) )
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# print( reverse(123) )
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# print( reverse(-123) )
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# print( reverse(2**31) )
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# print( reverse(-2**31) )
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