C++ stringstream problem

[thecoolman5]

hi, I am trying to make a calculator and I need the stringstream function to convert a a certain part of a string.

string n1 = "243+79";
int n2 = 0;
stringstream(n1[0-2]) >> n2; // this converts the 243 from n1 to an int

Any solutions?

[Nick Evan]

Have a look at the substr() function

[L7Sqr]

You can also think about strtol as a way to parse known good input.

[thecoolman5]

Have a look at the substr() function

Could you please explain how to use substr()? thanks

[thecoolman5]

Also, i need a function that can remove parts of a string.

[caut_baia]

std::string asd="234+34";
   char plus;
   int first,second;
   std::stringstream (asd) >> first >> plus >> second;

[Nick Evan]

Also, i need a function that can remove parts of a string.

That's what the substr() function does.

string n1 = "243+79";
    string first = n1.substr(0,3);
    string second = n1.substr(4,2);

In other words string.substr(starting_index, number_of_characters);

[thecoolman5]

Ok thanks for the help.