boost的函数:partition

template <typename ForwardIterator, typename Predicate> ForwardIterator partition_point ( ForwardIterator first, ForwardIterator last, Predicate p ) { std::size_t dist = std::distance ( first, last ); while ( first != last ) { std::size_t d2 = dist / 2; ForwardIterator ret_val = first; std::advance (ret_val, d2); if (p (*ret_val)) { first = ++ret_val; dist -= d2 + 1; } else { last = ret_val; dist = d2; } } return first; }

简介：二分法检测一组序列(针对当前的判断条件是有序的)中第一个不满足条件要求的元素

示例：

bool lessThan10(int i){return i < 10;} int myints_1[] = {0, 1, 3, 2, 14, 15, 1}; vector<int> c1(myints_1, myints_1 + sizeof(myints_1) / sizeof(int)); boost::algorithm::partition_point(c1, lessThan10); //14的迭代器 此函数功能的用途暂时无法清楚知道，可以与 is_partitioned 函数做对比。