Slicing

Slicing list

Slicing like this? No!
example

//Code==========
L = ['Bin', 'Lisa', 'Bart', 'Paul'] #wanna get front 2 element?
L2 = [L[0], L[1]] #NONONONONO
print (L2)
//Result==========
['Bin', 'Lisa']

Using slicing format
The first index is the index of first element you want to pick, and the second index is the next one of your last picked
example

//Code==========
L = ['Bin', 'Lisa', 'Bart', 'Paul'] #wanna get front 2 element?
L2 = L[0:2] # index of 0, 1, but stopped by 2 (won't be selected)
print (L2)
L3 = L[1:2] # index starting from 1, stopped by 2 (won't be selected)
print (L3)
L4 = L[:] # select all
print (L4)
L5 = L[::2] # from index 0, select one by skip one
print (L5)
//Result==========
['Bin', 'Lisa']
['Bin']
['Bin', 'Lisa', 'Bart', 'Paul']
['Bin', 'Bart']

Using slicing format with reverse order
negative index is also working well with slicing format
example

//Code==========
L = ['Bin', 'Lisa', 'Bart', 'Paul'] #wanna get front 2 element?
L2 = L[-2:] # index of -2 is `Bart`
print (L2)
L3 = L[0:-2] # index of -2 is `Bart`
print (L3)
L4 = L[-3:-1] # index of -3 is `Lisa`, index of -1 is 'Paul'
print (L4)
L5 = L[-4:-1:2] # index of -4 is `Bin`, index of -1 is 'Paul', 
# actually selecting from ['Bin', 'Lisa', 'Bart'], each time select one and skip next one
print (L5)
//Result==========
['Bart', 'Paul']
['Bin', 'Lisa']
['Lisa', 'Bart']
['Bin', 'Bart']

Slicing str

SAME TO LIST :)