C++之类型转换

1. string转int
string str;
int Num = atoi(str.c_str());

2.string转char*
string s = "how";
const char *c = s.c_str(); //或s.data();
3.in转string
#include <sstream>
string numToStr(int numn){
stringstream ss;
ss << numn;
string s2;
ss>>s2;
return s2;
}