Teaching Kids Programming: Videos on Data Structures and Algorithms
Introduction to Stack
Stack is an important and commonly-used data structure that implements First In Last Out. The first item gets pop-ed out at last and the last inserted item gets pop-ed out first.
st = []
st.append(1) # st = [1]
st.append(2) # st = [1, 2]
st.append(3) # st = [1, 2, 3]
x = st.pop() # x = 3, and st = [1, 2]
y = st.pop() # x = 2, and st = [1]
Reverse a List using Stack
A list in Python is inherent a Stack, which we can use the pop() to remove “last-inserted” item from the stack one by one and thus reversing the list.
def rev(nums):
ans = []
while len(nums) > 0:
x = nums.pop()
ans.append(x)
return ans
–EOF (The Ultimate Computing & Technology Blog) —
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