Subarrays and counting elements of subarrays python

Question

I have a program that finds the index of the largest value of an array and then from that point it splits it into two subarrays. Here's what it looks like:

def main():
   numbers = eval(input("Give me an array of numbers: "))
   largest = numbers[0]
   ind = numbers.index(max(numbers))
   print("Index of the largest number: ", ind)
   ar1, ar2 = numbers[0:ind], numbers[ind:]
   print("First subarray: ", ar1)
   print("Second subarray: ", ar2)
main()

Now I want it count the number of times the first value in the first subarray appears in the second subarray. How can I do that?

Possible _extension_ of http://stackoverflow.com/questions/23019773/locate-the-index-of-largest-value-in-an-array-python — devnull, Apr 11 '14 at 18:37
Do you want the largest number to be at the end of the first list or the beginning of the second list or just be removed? — s16h, Apr 11 '14 at 18:38
You use the code from the answers that you [receive](http://stackoverflow.com/questions/23019773/locate-the-index-of-largest-value-in-an-array-python) but still don't accept those? — devnull, Apr 11 '14 at 18:38
What kind of input are you expecting a user to give you for `eval(input('Give me an array of numbers: '))`? Because right now it would take a user typing _a valid Python list_ (not very user friendly) and of course is exposed to all the badness of `eval` (like the "array of number" `import os;os.system('rm -rf /')`) — Two-Bit Alchemist, Apr 11 '14 at 18:38

score 1 · Answer 1 · answered Apr 11 '14 at 18:34

1

Array slicing?

ar1, ar2 = numbers[0:ind], numbers[ind:]
print ar1
print ar2

answered Apr 11 '14 at 18:34

ajm475du

361
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score 0 · Answer 2 · answered Apr 11 '14 at 18:35

0

You can use slice:

print numbers[:ind], numbers[ind:]

numbers[:ind] prints elements from 0 to ind-1. numbers[ind:] prints elements from ind to last element

answered Apr 11 '14 at 18:35

venpa

4,268
21
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Subarrays and counting elements of subarrays python

2 Answers2