CCF认证2013122-ISBN号码

本人初学，水平有限，若有不足，恳请赐教！

具体代码如下：

#include <iostream>
#include <string>
#include <regex>

using namespace std;

int main()
{
	//FILE *stream;
	//freopen_s(&stream, "data.txt", "r", stdin);

	string s, t;
	cin >> s;
	t = regex_replace(s, regex("-"), ""); //将分隔符全部删除
	char key = t.back(); //提取识别码
	t.pop_back();
	s.pop_back();
	int sum = 0;
	for(int i = 0; i < 9; i++)
	{
		sum += (i + 1) * (t[i] - '0');
	}
	char cur = (sum % 11) + '0';
	if(!isdigit(cur)) cur = 'X';
	if(cur == key) cout << "Right";
	else cout << s << cur;

	//fclose(stream);

	return 0;
}