Wal*_*sen 9 c++ sorting string comparator
我想按照人类对它们进行排序的方式对字母数字字符串进行排序.即,"A2"出现在"A10"之前,"a"肯定出现在"Z"之前!没有编写迷你解析器,有什么办法吗？理想情况下,它也会将"A1B1"放在"A1B10"之前.我在可能的答案中看到了"Microsoft SQL 2005中的自然(人类字母 - 数字)排序"这一问题,但它使用了各种库函数,"使用IComparer为人类排序字符串"也是如此.
以下是目前失败的测试用例:
#include <set>
#include <iterator>
#include <iostream>
#include <vector>
#include <cassert>
template <typename T>
struct LexicographicSort {
inline bool operator() (const T& lhs, const T& rhs) const{
std::ostringstream s1,s2;
s1 << toLower(lhs); s2 << toLower(rhs);
bool less = s1.str() < s2.str();
//Answer: bool less = doj::alphanum_less<std::string>()(s1.str(), s2.str());
std::cout<<s1.str()<<" "<<s2.str()<<" "<<less<<"\n";
return less;
}
inline std::string toLower(const std::string& str) const {
std::string newString("");
for (std::string::const_iterator charIt = str.begin();
charIt!=str.end();++charIt) {
newString.push_back(std::tolower(*charIt));
}
return newString;
}
};
int main(void) {
const std::string reference[5] = {"ab","B","c1","c2","c10"};
std::vector<std::string> referenceStrings(&(reference[0]), &(reference[5]));
//Insert in reverse order so we know they get sorted
std::set<std::string,LexicographicSort<std::string> > strings(referenceStrings.rbegin(), referenceStrings.rend());
std::cout<<"Items:\n";
std::copy(strings.begin(), strings.end(), std::ostream_iterator<std::string>(std::cout, "\n"));
std::vector<std::string> sortedStrings(strings.begin(), strings.end());
assert(sortedStrings == referenceStrings);
}