1 #include<iostream>
 2 #include<string>
 3 #include<vector>
 4 #include <stack>
 5 #include <algorithm>
 6 
 7 using namespace std;
 8 
 9 
10 int main()
11 {
12     vector<int> vec{ 1,2,3,4,5,6,7,8,9,10,1,2,3,5,6,7,89,6,4,2,3,15,5,6,45 };
13     int val = 11;
14     auto a_num = count(vec.begin(), vec.end(), val);
15     cout << a_num << endl;
16     system("pause");
17     return 0;
18 }

 1 #include<iostream>
 2 #include<string>
 3 #include<vector>
 4 #include <stack>
 5 #include <algorithm>
 6 #include <list>
 7 
 8 using namespace std;
 9 
10 
11 int main()
12 {
13     list<string> vec;
14     string word;
15     while (cin >> word)
16         vec.push_back(word);
17     string val = "123";
18     auto a_num = count(vec.begin(), vec.end(), val);
19     cout << a_num << endl;
20     system("pause");
21     return 0;
22 }