C++ vector 容器

 1 //vector类  resemble array  自动扩容...  暂存于内存中
 2 //格式 vector<类（型）名> 对象名  example: vector<string> v; vector<int> i;
 3 //copy a entire file into a vector of string
 4 #include<fstream>
 5 #include<string>
 6 #include<iostream>
 7 #include<vector>
 8 using namespace std;
 9 int main()
10 {
11  vector<string> v;
12  string  s;
13  ofstream out("file.txt");
14  for (int i = 0; i < 3; i++)
15  {
16   cout << "Please enter:" << endl;
17   getline(cin, s);
18   out << s << '
';
19  }
20  out.close();
21  ifstream in("file.txt");
22  while (getline(in, s))//按行读取
23   v.push_back(s);  //将string s压入vector v的尾部
24  for (int i = 0; i < v.size(); i++)
25   cout <<i<<":"<< v[i] << endl;
26  for (int i = 0; i < v.size(); i++)
27   v[i] += "!";//可以根据下标改变单元的值
28  for (int i = 0; i < v.size(); i++)
29   cout << i << ":" << v[i] << endl;
30  system("pause");
31  return 0;
32 }