world!, I ran into a problem earlier today… I am trying to split operations apart from digits and variables. it’ll split +,-,/,* apart from the digits or the variable (ex: 10+11+10 goes in the code and a list comes out with ["10","+","11","+","10"])

My code:

x = "100+20+a"

operators = ["*","/","+","-"]

def get_index_of(OP,txt):
  return [v for v,i in enumerate(txt+"+") if i == OP]

l = []
for i in operators:
  l.append(get_index_of(i,x))

spliting = sum(l,[])

out = []
for j in spliting:
  out.append(x)
  x = x[:j]

print(out)

The output I get:

['100+20+a', '100', '100']

The output I want:

["100","+","20","+","a"]

>Solution :

Using stack

def parse(expression, operators = ["*","/","+","-"]):
    stack = ['']               # start with empty string on stack
    for c in expression:
        if c in operators:
            stack.append(c)    # place operator as new element on stack
            stack.append('')
        elif c != " ":         # not a space
            stack[-1] += c     # append to last element on stack
            
    return stack

Example

print(parse("100+20+a"))
# Output: ['100', '+', '20', '+', 'a']