你爱西加加么?
cin
int a;
cin >> a;
cout
int a = 5;
cout << a << endl; // endl : '\n'
vector
vector<int> a;
vector<int> b(5); //定义一维动态数组含有五个元素
vector<vector<int> > obj(5, vector<int>(6)); //定义二维动态数组5行6列
a.push_back(2);
int r = a[0];
a.pop_back();
a.clear();
string
string a;
a = "Do you like c++?";
int len = a.length();
char x = a.at(0);
a = "123";
int number = stoi(a); // number = 123
string a2 = a.substr(0,2); // a2 = "12"
a = a + "45";
int n = 123;
string mystring = to_string(n);