Im having trouble with an assignment where I have to convert three variables of a clock (int hour, int minutes, and bool afternoon) to be converted to a string in a method. I tried converting the int to a char and then replacing each string with the char. The function is suppose to return T/F if the conversion worked or not. Here is what I have so far:
class Time { private: int hour; int minutes; bool afternoon; public: void setHour(int hr); void setMinutes(int min); void setAfternoon(bool aft); int getHour(); int getMinutes(); bool getAfternoon(); bool setAsString(string time); string getAsString(); Time(void); ~Time(void); };
and
bool Time::setAsString(string time){ char min = minutes; char hr = hour; char hr[0] = time[0]; char hr[1]= time[1]; char min[0] = time[3]; char min[1] = time[4]; char afternoon = time[6]; if ((hourTens > 1) || (minTens > 5)) { return false; } else { return true; } } string Time::getAsString(){ return false; }
it is straight-forward in fact, but may involve a little twist in mind at first.
I am not going to give you the actual code, but some snippet that, if you can understand them, you should be able to solve the problem by yourself:
What you want to do is converting an integer to a string/char. The most basic thing you need to do is to convert a single digit int to corresponding char.
// for example you have such integer int i = 3; // and you want to convert it to a char so that char c = '3';
what you need to do is, by adding i to '0'. The reason why it works is because '0' actually means an integer value of 48. '1'..'9' means 49..57. This is a simple addition to find out corresponding character for an single decimal digit integer:
i.e. char c = '0' + i;
If you know how to convert a single decimal digit int to char, what's left is how you can extract individual digit from a more-than-one-decimal-digit integer
it is simply a simple math by making use of / and %
int i = 123 % 10; // give u last digit, which is 3 int j = 123 / 10; // give remove the last digit, which is 12
The logic left is the homework you need to do then.
Assuming you want to manually convert each char into an int, here is a very rough idea. Use a switch statement to convert each char into its ascii value. For example, switch(char_to_convert)'s case 38 would return 1. Basically, "1" converted to ASCII is 49(Thank you Ben Voigt for the correction). You don't actually need to convert it; you compiler will notice and convert it for you. Then you make the comparisons. See Ascii Table for a complete list.
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