C++中关联容器的问题，，，，，，，

Question

#include
#include
#include

int main ()
{
std::string s ("this subject has a submarine as a subsequence");
std::smatch m;
std::regex e ("\b(sub)([^ ]*)"); // matches words beginning by "sub"

std::cout << "Target sequence: " << s << std::endl;
std::cout << "Regular expression: /\b(sub)([^ ]*)/" << std::endl;
std::cout << "The following matches and submatches were found:" << std::endl;

while (std::regex_search (s,m,e)) {
for (auto x:m) std::cout << x << " ";
std::cout << std::endl;
s = m.suffix().str();
}

return 0;
}

while循环中的流程不理解

Answer 1

 这里是使用了正则表达式，之所以你不懂，估计是不了解正则表达式。
 ("\b(sub)([^ ]*)");
 这里匹配以sub开头的单词。
while (std::regex_search (s,m,e)) 
这里是一个迭代器，依次返回匹配到的子串。