我有这个功能:
template<typename T>
void Inventory::insertItem(std::vector<T>& v, const T& x)
{
std::vector<T>::iterator it; // doesn't compile
for(it=v.begin(); it<v.end(); ++it)
{
if(x <= *it) // if the insertee is alphabetically less than this index
{
v.insert(it, x);
}
}
}
和g ++给出了这些错误:
src/Item.hpp: In member function ‘void
yarl::item::Inventory::insertItem(std::vector<T, std::allocator<_CharT> >&, const T&)’:
src/Item.hpp:186: error: expected ‘;’ before ‘it’
src/Item.hpp:187: error: ‘it’ was not declared in this scope
它必须是简单的东西,但在盯着它十分钟后我找不到任何错误。其他人都看到了吗?
答案 0 :(得分:31)
答案 1 :(得分:8)
你在做什么效率低下。改为使用二进制搜索:
#include <algorithm>
template <typename T>
void insertItem(std::vector<T>& v, const T& x)
{
v.insert(std::upper_bound(v.begin(), v.end(), x), x);
}