All possibilities to put +, - or nothing between numbers to get sum equal to 100

Question

I have to built a function which would list the all possibilities to put +, - or nothing between the numbers ranging from 1 to 9 and print it result.

For example: 1

Answer 1

def hun(exp, i):
        if (i<=9):
                for mark in ("+", "-", ""):
                        hun(exp + mark + str(i), i+1)
        elif eval(exp) == 100:
                print(exp + " = 100")
hun("1",2)