资料来源: https://www.geeksforgeeks.org/initialize-a-vector-in-cpp-different-ways/

push_back初始化法

  1. // CPP program to create an empty vector 
  2. // and push values one by one. 
  3. #include <bits/stdc++.h> 
  4. using namespace std; 
  6. int main() 
  7. { 
  8.     // Create an empty vector 
  9.     vector<int> vect; 
  11.     vect.push_back(10); 
  12.     vect.push_back(20); 
  13.     vect.push_back(30); 
  15.     for (int x : vect) 
  16.         cout << x << " "; 
  18.     return 0; 
  19. }

初始值初始空间法

  1. // CPP program to create an empty vector 
  2. // and push values one by one. 
  3. #include <bits/stdc++.h> 
  4. using namespace std; 
  6. int main() 
  7. { 
  8.     int n = 3; 
  10.     // Create a vector of size n with 
  11.     // all values as 10. 
  12.     vector<int> vect(n, 10); 
  14.     for (int x : vect) 
  15.         cout << x << " "; 
  17.     return 0; 
  18. }

初始值法

  1. // CPP program to initialize a vector like 
  2. // an array. 
  3. #include <bits/stdc++.h> 
  4. using namespace std; 
  6. int main() 
  7. { 
  8.     vector<int> vect{ 10, 20, 30 }; 
  10.     for (int x : vect) 
  11.         cout << x << " "; 
  13.     return 0; 
  14. }

拷贝其它Vector

// CPP program to initialize a vector from 
// an array. 
#include <bits/stdc++.h> 
using namespace std; 

int main() 
{ 
    int arr[] = { 10, 20, 30 }; 
    int n = sizeof(arr) / sizeof(arr[0]); 

    vector<int> vect(arr, arr + n); 

    for (int x : vect) 
        cout << x << " "; 

    return 0; 
}

迭代器拷贝其它Vector

// CPP program to initialize a vector from 
// another vector. 
#include <bits/stdc++.h> 
using namespace std; 

int main() 
{ 
    vector<int> vect1{ 10, 20, 30 }; 

    vector<int> vect2(vect1.begin(), vect1.end()); 

    for (int x : vect2) 
        cout << x << " "; 

    return 0; 
}