tokenizer

Hi, I have string line("a_1 = b_1 ( c_2 )") tokenizer< > tok(line); for (tokenizer<>::iterator beg=tok.begin(); beg!=tok.end();++beg) { cout << *beg << endl; }  gives me a 1 b 1 c 2 I want to be able to specify delimiters like in strtok so that I get a_1, b_1 and c_2 but couldn't figure out how to specify the tokenizer function. Any suggestions? Regards Rajesh