I have a byte array (vector <char> and I want to copy each byte to string):
The code:
The program crashes at the copy line.. What am I doing wrong?Code:using namespaces std; vector <char> v; v.resize(20); //..fill the vector.. // now copy string str; copy(v.begin(), v.end(), str.begin());
something's probably wrong in the "fill the vector" section of your code. It should work
Regardless:
Remove that 's'Code:using namespaces std;
Originally Posted by brewbuck:
Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.
Code:int main( void ) { std::vector <char> v; for ( int i='a'; i<'n'; i++ ) v.push_back( i ); std::string str; str.insert( str.begin(), v.begin(), v.end() ); std::cout<< '\n' << str; return 0; }
Last edited by twomers; 09-25-2006 at 12:04 PM.
Or... much easier, you can build the string from the vector using one of the constructor overloads.
Code:string str(v.begin(), v.end());
Originally Posted by brewbuck:
Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.
Nice!! I didn't know that!! Shame it's not (yet) possible to do it the other way around :/Originally Posted by Mario F.
Code:string str = "aaaaaaaaaa"; vector<char> v(str.begin(), str.end());
Originally Posted by brewbuck:
Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.
FWIW, with a slight modification the original copy function could have been used as well.
Code:// now copy string str; copy(v.begin(), v.end(), inserter(str,str.end()) );
"Owners of dogs will have noticed that, if you provide them with food and water and shelter and affection, they will think you are god. Whereas owners of cats are compelled to realize that, if you provide them with food and water and shelter and affection, they draw the conclusion that they are gods."
-Christopher Hitchens
Yes. I was actually trying to understand why it wasn't working and experienced a situation where the copy does apparently nothing.
I'm not familiar with that function but I guess it returns an insert iterator, correct?
Cppreference makes no mention to the fact the last argument needs to be one, it seems.
Originally Posted by brewbuck:
Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.
