#include <iostream>
#include <string>
#include <algorithm>

using namespace std;

int main(int argc, char const *argv[])
{

    std::string s("a,b,c,d,e,f,");

	std::replace_if(s.begin(), s.end(), [](char c){return c == ','; }, ' ');
	cout << s << endl;

    return 0;
}