Discounted Price Help

instructions:
First item price stays the same, every price after is reduced by the lesser items cost (never below 0)

my code:
INTEGER_ARRAY = [4,4,9,2,3]
def calculateAmount(prices):
i = 1
while i < len(INTEGER_ARRAY):
i += 1
LONG_INTEGER = INTEGER_ARRAY[0]
LONG_INTEGER = LONG_INTEGER +(INTEGER_ARRAY[i] - (min(INTEGER_ARRAY))
return LONG_INTEGER
calculateAmount(INTEGER_ARRAY)

I keep getting the wrong results