I'm assuming the goal of your program is to add all inputs, to see if you get a total value = 1, if this is the case; All your inputs are of a string datatype and not what they're supposed to be, which is integers, since you're adding them. Lets say the user gives all your variables these values as inputs
E_String = "1" A_String = "0" D_String = "0" G_String = "0" B_String = "0" e_String = "0"Since input() accepts it as a string, your variable all_string_sum is essentially adding "1" + "0" + "0"...etc to give a combined string of "100000". What you need to do is convert your input to accept user values as integers, which you can do by modifying your code as such:
E_String = int(input('What are you fretting on the low E string? ')) A_String = int(input('What are you fretting on the A string? ')) D_String = int(input('What are you fretting on the D string? ')) G_String = int(input('What are you fretting on the G string? ')) B_String = int(input('What are you fretting on the B string? ')) e_String = int(input('What are you fretting on the high e string? ')) all_string_sum = (E_String + A_String + D_String + G_String + B_String + e_String) if all_string_sum == 1: print ("E")Good rule of thumb when debugging is to check what your variable holds, by printing it.