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pythontypesargumentsxrange

Why does Python say "Inappropriate Argument Type" for xrange?

My code is:

def euler7():
    prime=1
    val=0
    for num in xrange(3, 9999999999, 2):
        for n in xrange(1, num):
            if num%n==0:
                numb=0
                break
            else:
                numb=1
                val=num
            if numb==1:
                prime=prime+1
            if prime==10001:
                return val

But, it says there is an Inappropriate argument type for the for loops. I dont know if that means that it is not seeing the values as integers, or what is happening. Thanks

Solution

  • xrange won't work with large numbers since the code is executed as a C program (https://docs.python.org/2/library/functions.html#xrange).

    According to docs -

    CPython implementation detail: xrange() is intended to be simple and fast. Implementations may impose restrictions to achieve this. The C implementation of Python restricts all arguments to native C longs (“short” Python integers), and also requires that the number of elements fit in a native C long. If a larger range is needed, an alternate version can be crafted using the itertools module: islice(count(start, step), (stop-start+step-1+2*(step<0))//step).

    I am not sure what system specs you got, but generally c int is 2^16-1 and c long is 2^32-1.