使 vector中的class 按照自己的要求排序

class IndexToPG{public: int m_iIndex;double m_dPGScore;IndexToPG(int index,double score){ m_iIndex = index;m_dPGScore = score;}};//binary function predicate, used to sort the IndexToPG object, decrease order by pgScorebool IndexToPGSortScoreDec(const IndexToPG& item1, const IndexToPG& item2){return item1.m_dPGScore > item2.m_dPGScore;}vector<IndexToPG> tempCollection;sort(tempCollection.begin(),tempCollection.end(),IndexToPGSortScoreDec);