#include <iostream> #include <vector>

int main() { vector<int> v1; // 创建一个空的存储int类型元素的vector return 0; } #include <iostream> #include <vector> int main() { vector<int> v2(5); // 创建包含5个元素的vector，元素初始值为0 for (int i = 0; i < v2.size(); ++i) { cout << v2[i] << " "; } cout << endl; return 0; } #include <iostream> #include <vector>

int main() { vector<int> v3(5, 10); // 创建包含5个元素的vector，每个元素初始值为10 for (int i = 0; i < v3.size(); ++i) { cout << v3[i] << " "; } cout << endl; return 0; } #include <iostream> #include <vector>

int main() { vector<int> v4 = {1, 2, 3, 4, 5}; // 使用列表初始化vector for (int i = 0; i < v4.size(); ++i) { cout << v4[i] << " "; } cout << endl; return 0; } #include <iostream> #include <vector>

int main() { vector<int> v; v.push_back(1); v.push_back(2); for (int i = 0; i < v.size(); ++i) { cout << v[i] << " "; } cout << endl; return 0; } #include <iostream> #include <vector>

int main() { vector<int> v = {1, 2, 3}; // 使用下标访问 cout << v[1] << endl; // 使用迭代器访问 for (vector<int>::iterator it = v.begin(); it != v.end(); ++it) { cout << *it << " "; } cout << endl; return 0; } #include <iostream> #include <vector> int main() { vector<int> v = {1, 2, 3, 4, 5}; v.pop_back(); // 删除末尾元素 v.erase(v.begin() + 1); // 删除索引为1的元素 for (int i = 0; i < v.size(); ++i) { cout << v[i] << " "; } cout << endl; return 0; } #include <iostream> #include <vector>

int main() { vector<vector<int>> v1; // 创建一个空的二维vector vector<int> row1 = {1, 2, 3}; vector<int> row2 = {4, 5, 6}; v1.push_back(row1); v1.push_back(row2); return 0; } #include <iostream> #include <vector>

int main() { int rows = 3; int cols = 4; vector<vector<int>> v2(rows, vector<int>(cols)); // 创建3行4列的二维vector，元素初始值为0 for (int i = 0; i < rows; ++i) { for (int j = 0; j < cols; ++j) { cout << v2[i][j] << " "; } cout << endl; } return 0; } #include <iostream> #include <vector>

int main() { int rows = 3; int cols = 4; int initValue = 1; vector<vector<int>> v3(rows, vector<int>(cols, initValue)); // 创建3行4列的二维vector，元素初始值为1 for (int i = 0; i < rows; ++i) { for (int j = 0; j < cols; ++j) { cout << v3[i][j] << " "; } cout << endl; } return 0; } #include <iostream> #include <vector> int main() { vector<vector<int>> v = {{1, 2}, {3, 4}}; cout << v[1][0] << endl; // 输出3 return 0; } #include <iostream> #include <vector>

int main() { vector<vector<int>> v = {{1, 2}, {3, 4}}; v[1][0] = 10; cout << v[1][0] << endl; // 输出10 return 0; } #include <iostream> #include <vector>

int main() { vector<vector<int>> v = {{1, 2}, {3, 4}}; vector<int> newRow = {5, 6}; v.push_back(newRow); for (int i = 0; i < v.size(); ++i) { for (int j = 0; j < v[i].size(); ++j) { cout << v[i][j] << " "; } cout << endl; } return 0; }