List Operations, Functions and Methods

List Operations, Functions and Methods

A list is a mutable, ordered sequence. It supports concatenation (+), repetition (*), membership (in) and slicing, just like a string, and its elements can be changed in place.

• Built-in functions: len(), list(), min(), max(), sum(), sorted() (returns a new sorted list).
• Methods that change the list: append(), extend(), insert(), remove(), pop(), reverse(), sort().
• Methods that only look: count(), index().

a = [3, 1, 2]
b = sorted(a)      # a is unchanged: [3, 1, 2]; b is [1, 2, 3]
a.sort()           # a itself is now [1, 2, 3]; sort() returns None
a.extend([5, 4])   # [1, 2, 3, 5, 4]
a.append([6])      # [1, 2, 3, 5, 4, [6]]: one element, a list
m = [[1, 2], [3, 4]]
print(m[1][0])     # 3: nested list, row 1, column 0

Because lists are mutable, b = a does not copy the list: both names refer to one list. Use a.copy(), list(a) or a[:] for a real copy.

nums = list(map(int, input().split()))
big = small = nums[0]
total = 0
for n in nums:
    pass  # update big, small and total
print(big, small, f"{total / len(nums):.2f}")