How can I split a string such as "102:330:3133:76531:451:000:12:44412 by the ":" character, and put all of the numbers into an int array (number sequence will always be 8 elements long)? Preferably without using an external library such as boost.
Also, I'm wondering how I can remove unneeded characters from the string before it's processed such as "$" and "#"?
stringstream can do all these.
Split a string and store into int array:
string str = "102:330:3133:76531:451:000:12:44412"; std::replace(str.begin(), str.end(), ':', ' '); // replace ':' by ' ' vector<int> array; stringstream ss(str); int temp; while (ss >> temp) array.push_back(temp); // done! now array={102,330,3133,76531,451,000,12,44412} Remove unneeded characters from the string before it's processed such as $ and #: just as the way handling : in the above.
PS: The above solution works only for strings that don't contain spaces. To handle strings with spaces, please refer to here based on std::string::find() and std::string::substr().
std::replace(str.begin(), str.end(), ':', ' ');
The standard way in C is to use strtok like others have answered. However strtok is not C++-like and also unsafe. The standard way in C++ is to use std::istringstream
std::istringstream iss(str); char c; // dummy character for the colon int a[8]; iss >> a[0]; for (int i = 1; i < 8; i++) iss >> c >> a[i]; In case the input always has a fixed number of tokens like that, sscanf may be another simple solution
std::sscanf(str, "%d:%d:%d:%d:%d:%d:%d:%d", &a1, &a2, &a3, &a4, &a5, &a6, &a7, &a8); I had to write some code like this before and found a question on Stack Overflow for splitting a string by delimiter. Here's the original question: link.
You could use this with std::stoi for building the vector.
std::vector<int> split(const std::string &s, char delim) { std::vector<int> elems; std::stringstream ss(s); std::string number; while(std::getline(ss, number, delim)) { elems.push_back(std::stoi(number)); } return elems; } // use with: const std::string numbers("102:330:3133:76531:451:000:12:44412"); std::vector<int> numbers = split(numbers, ':'); 
True ! there's no elven magic
Its kinda answered here too
#include <cstring> #include <iostream> #include<cstdlib> #include<vector> int main() { char input[100] = "102:330:3133:76531:451:000:12:44412"; char *token = std::strtok(input, ":"); std::vector<int> v; while (token != NULL) { v.push_back( std::strtol( token, NULL, 10 )); token = std::strtok(NULL, ":"); } for(std::size_t i =0 ; i < v.size() ; ++i) std::cout << v[i] <<std::endl; } Demo Here
To remove characters '#' and '$' you can use standard algorithm std::remove_if. However take into account that if there is for example the following string "12#34" then after removing '#' you will ge "1234". If you need that the resulted string will look as "12 34" or "12:34" then instead of std::remove_if it is better to use std::replace_if.
Below there is a sample code that performs the task. You need to include headers
#include <iostream> #include <cstdlib> #include <cstring> #include <algorithm> int main() { char s[] = "102:$$330:#3133:76531:451:000:$12:44412"; std::cout << s << std::endl; char *p = std::remove_if( s, s + std::strlen( s ), []( char c ) { return ( c == '$' || c == '#' ); } ); *p = '\0'; std::cout << s << std::endl; const size_t N = 8; int a[N]; p = s; for ( size_t i = 0; i < N; i++ ) { a[i] = strtol( p, &p, 10 ); if ( *p == ':' ) ++p; } for ( int x : a ) std::cout << x << ' '; std::cout << std::endl; } The output is
102:$$330:#3133:76531:451:000:$12:44412 102:330:3133:76531:451:000:12:44412 102 330 3133 76531 451 0 12 44412 Here's one way... not the cleverest but fast to write (8 repetition's verging on warranting a loop though). This approach to parsing is quite widely useful so good to learn. !(iss >> c) ensures there's no trailing non-whitespace characters in the string.
std::istringstream iss(the_string); char c; int n[8]; if (iss >> n[0] >> c && c == ':' && iss >> n[1] >> c && c == ':' && iss >> n[2] >> c && c == ':' && iss >> n[3] >> c && c == ':' && iss >> n[4] >> c && c == ':' && iss >> n[5] >> c && c == ':' && iss >> n[6] >> c && c == ':' && iss >> n[7] && !(iss >> c)) ... 
c == ':'?
[ 3 14 2 78 99 1 8 6 ] otherwise. (I get really tired of seeing S.O. questions where I/O problems would have been found if people checking input and output properly).#include <sstream>?You can use strtok() for split your string, perhaps in while loop.
When you get individual string then can use atoi(xxx) for conversion in ints.
Another solution using the regular expression features in C++11.
#include <algorithm> #include <iostream> #include <iterator> #include <ostream> #include <regex> #include <sstream> #include <string> #include <vector> int main() { const std::string s = "102:330:3133:76531:451:000:12:44412"; // Replace each colon with a single space const std::regex pattern(":"); const std::string r = std::regex_replace(s, pattern, " "); std::istringstream ist(r); std::vector<int> numbers; std::copy(std::istream_iterator<int>(ist), std::istream_iterator<int>(), std::back_inserter(numbers)); // We now have a vector of numbers // Print it out for (auto n : numbers) { std::cout << n << " "; } std::cout << std::endl; return 0; } 
#include <stdio.h> #include <string.h> int main () { char str[] ="102:330:3133:76531:451:000:12:44412"; char * pch; printf ("Splitting string \"%s\" into tokens:\n",str); pch = strtok (str,":"); while (pch != NULL) { printf ("%s\n",pch); pch = strtok (NULL, ":"); } return 0; } 
elven magicyou are using