python How to delete characters before a specified position in such as 21-2 Delete - All preceding characters ？
s = "21-2"
# Method 1 （ Universal ）
# find ‘-’ The index of the value , Then add one to get the value after the minus sign
index = s.find('-')+1
print(s[index:])
# Method 2 （ Manual calculation is cheap ）
# Number offset
print(s[3:])
# Method 3 （ Clever , utilize - Separate ）
# has ‘-’ Separator , Take the following content
print(s.split('-')[1])
