boost::algorithm::replace_nth_copy — 替换第 n 个算法。
// In header: <boost/algorithm/string/replace.hpp> template<typename OutputIteratorT, typename Range1T, typename Range2T, typename Range3T> OutputIteratorT replace_nth_copy(OutputIteratorT Output, const Range1T & Input, const Range2T & Search, int Nth, const Range3T & Format); template<typename SequenceT, typename Range1T, typename Range2T> SequenceT replace_nth_copy(const SequenceT & Input, const Range1T & Search, int Nth, const Range2T & Format);