C++ string int转换

#include <iostream>
#include <string>
using namespace std;

int a = 10;
string s = to_string(a);
int b = atoi("1010");

mfc  CString int 
int numin = 100;
int numout = 200;
CString strin,strout;
strin.Format("%d", numin);
strout.Format("%d", numout);

strin = L"10";
int numx = _ttoi(strin);