file hello.cpp update

+#include<iostream>
+#include<string>
+using namespace std;
+
+int main() 
+{
+	cout << "강의영상 1:30 부터인가 싱크 안맞아요" << endl;
+
+	string com;
+	cout << ">";
+	cin >> com;
+	
+	if(com=="exit")	
+		exit(0);
+
+	return 0;
+}
\ No newline at end of file