public class Solution {

    public IList<int> DiffWaysToCompute(string input) {

        List<int> ret = new List<int>();

            for (int i = ; i < input.Length; i++)

            {

                if (input[i] == '-' ||

                    input[i] == '*' ||

                    input[i] == '+')

                {

                    string part1 = input.Substring(, i);

                    string part2 = input.Substring(i + );

                    var part1Ret = DiffWaysToCompute(part1);

                    var part2Ret = DiffWaysToCompute(part2);

                    foreach (var p1 in part1Ret)

                    {

                        foreach (var p2 in part2Ret)

                        {

                            int c = ;

                            switch (input[i])

                            {

                                case '+': c = p1 + p2;

                                    break;

                                case '-': c = p1 - p2;

                                    break;

                                case '*': c = p1 * p2;

                                    break;

                            }

                            ret.Add(c);

                        }

                    }

                }

            }

            if (ret.Count == )

            {

                ret.Add(int.Parse(input));

            }

            return ret;

    }

}

 class Solution:

     def diffWaysToCompute(self, input: str) -> 'List[int]':

         re = list()

         n = len(input)

         for i in range(n):

             c = input[i]

             if c =='+' or c == '-' or c == '*':

                 left = input[:i]

                 right = input[i+:]

                 for l in self.diffWaysToCompute(left):

                     for r in self.diffWaysToCompute(right):

                         if c == '+':

                             re.append(l + r)

                         elif c == '-':

                             re.append(l -  r)

                         elif c == '*':

                             re.append(l * r)

         if len(re) == :

             re.append(int(input))

         return re