unsupported operand type(s) for : 'int' and 'str' [TypeError]-CodePudding

I am currently learning Python so I have no idea what is going on.

    # Given N, Amount of money in the house. Adjacent houses can't be stolen. Find the max amount that can be stolen
    # 6,7,1,30,8,2,4
    numbers = input()
    n = numbers.split(",")
    t = numbers.count(",")
    def rob(nums, i):
        if i <= 0:
            return 0
        return max(rob(nums, i-2)   nums[i], rob(nums, i-1))
    print(rob(n, t))

When I run the program, entering in numbers for Num and I, it returns this:

   TypeError: unsupported operand type(s) for  : 'int' and 'str'

CodePudding user response：

The values in the n array are of type 'str', not 'int'. This is because the .split method returns type 'str' You need to convert them to 'int' in order to do the mathematical operations as you intend. Something like this:

n = [int(val) for val in n]

Put this after the line where n is initialized.

CodePudding user response：

To solve the type error, you need to do as follows in the return line:

return max(rob(nums, i-2)   int(nums[i]), rob(nums, i-1))

The problem is that you are adding the return value of rob(nums, i-2) to the value nums[i] which is a string, and addition of an int to string is undefined. Note that the split function returns a list of strings (which is what n is in your code).

Furthermore, I know you were not asking about whether the algorithm works or not, but for input 30,1,1,30 your code outputs 31, but the max that can be stolen is 60.