C++ 访问vector数组头尾的四种方法

void vecInOutPut(std::vector<int>& vec_test)
{if (vec_test.size() > 2){//下标cout << vec_test[0] << endl;cout << vec_test[vec_test.size()-1] << endl;//atcout << vec_test.at(0) << endl;cout << vec_test.at(vec_test.size()-1) << endl;//front,back函数cout << vec_test.front() << endl;cout << vec_test.back() << endl;//指针std::vector<int>::iterator Begin = vec_test.begin();std::vector<int>::iterator end = vec_test.end()-1;cout << *Begin << endl;cout << *end << endl;}
}