C++ Help

[AbstractionAnon]

Line 19: number_string[0-2] are chars, not integers. You're adding the ASCII values of the chars together.

[a00]

the problem occur at total = number_string[0] + number_string[1] + number_string[2];. number_string[0] is a character. it have a ascii value for its corresponding character. if you want to let it become an actual number for the character just minus '0' to number_string[0] . since you have three number_string so you have to subtract 3 * '0'. replace your original statement to this. total = number_string[0] + number_string[1] + number_string[2] - 3 * '0';

[a00]

consider you number_string[0] is '1' after input. '1' has ascii value 49(in decimal) and '0' has ascii value 48(in decimal). you use '1' - '0' can actually get 1. since the ascii is placed in order that smaller number in former. larger number in later. for example '0' is 48(in decimal). '1' is 49(in decimal). '2' is 50(in decimal) and so on to '9' is 57(in decimal). since the order of the character. you can apply this to other character. '2' - '0' is 50 - 48. it is equal 2 and so on. c++ do the implicit conversion for you.