Re: Problem with string parameters
Gaijinco je napisao:
I made this function which given two strings c1 and c2 test if with the
letters of both you can exactly form the string c3, so for exaple c1 =
"evol" c2= "ution" and c3 = "evolution" will yield true.
The function looks like this:
#include <iostream>
#include <algorithm>
#include <string>
using namespace std;
bool areSubComp(string c1, string c2, string c3)
{
c1+=c2;
sort(c1.begin(),c1.end());
sort(c3.begin(),c3.end());
if(c1==c3)
return true;
else
return false;
}
int main()
{
cout << areSubComp("eouio","vltn","evolution"); // line 19
return 0;
}
I was trying to pass the last two arguments as reference to avoid the
copy of both strings using:
bool areSubComp(string c1, string& c2, string& c3)
but the compiler gives me this error:
line 19: cannot convert parameter 2 from 'char [5]' to 'class
std::basic_string<char,struct std::char_traits<char>,class
std::allocator<char> > &'
What's wrong and how can I accomplish what I wanted to?
Thanks.
Note that "eouio" is constant string - you can not legaly change
values.
One solution is to make params const:
bool areSubComp(string c1, const string&c2, const string& c3);
Than, compiler will make temprary string. This solution raise new
problem - you can not sort const data! So, you can make new copy into
temp variables, but this will end like starting code (you do not wanna
copy).
If your code do not need speed just leave it - string copy is not so
expensive.
If speed metters: you can use char* whit your or std::qsort sorting
Best,
Zahaije Pasalic