cpp-learn.tar.gz

#include <iostream> #include <string> #include <vector> #include <algorithm> #include <cstring> using namespace std; class Teacher { public: Teacher(const char* name = "", int age = 32) { strcpy(this->name, name); this->age = age; } void printInfo() { cout << "name:" << name << ", age:" << age << endl; } private: int age; char name[64]; }; void use_vector_Teacher() { vector<Teacher*> vec; vector<Teacher*>::iterator it; Teacher t1("t1", 21); Teacher t2("t2", 31); Teacher t3("t3", 41); vec.push_back(&t1); vec.push_back(&t2); vec.push_back(&t3); for (it = vec.begin(); it != vec.end(); it++) { (*it)->printInfo(); } } template <typename T> void print_vector(const vector<T>& v) { for (int i = 0; i < v.size(); i++) { cout << v.at(i) << " "; } cout << endl; } void use_vector_int1() { vector<int> vec; vector<int>::iterator it; vec.push_back(1); vec.push_back(3); vec.push_back(5); for (it = vec.begin(); it != vec.end(); it++) { cout << *it << endl; } } void use_vector_int2() { vector<int> vec; vector<int>::iterator it; vec.push_back(1); vec.push_back(3); vec.push_back(5); for (int i = 0; i < vec.size(); i++) { cout << vec.at(i) << " "; } cout << endl; vector<int> v2(vec.begin(), vec.begin() + 2); for (int i = 0; i < v2.size(); i++) { cout << v2[i] << " "; } cout << endl; // cout << "front=" << vec.front() << endl; // vec.front() = 22; // cout << "front=" << vec.front() << endl; // vec.back() = 55; // while (vec.size() > 0) // { // cout << vec.back() << endl; // vec.pop_back(); // } } void use_vector_int3() { vector<int> vec(10); cout << "size=" << vec.size() << endl; printf("&front=%p\n", &(vec.front())); for (int i = 0; i < vec.size(); i++) { vec[i] = (i + 1) * (i + 1); } vec.push_back(100); vec.push_back(200); cout << "size=" << vec.size() << endl; printf("&front=%p\n", &(vec.front())); for (int i = 0; i < vec.size(); i++) { cout << vec.at(i) << endl; } printf("back:%p\n", &(vec.back())); printf("back mem:%p\n", &vec[vec.size() - 1]); } void use_vector_int4() { vector<int> vec(10); for (int i = 0; i < vec.size(); i++) { vec[i] = (i + 1) * (i + 1); } print_vector<int>(vec); cout << "order print" << endl; for (vector<int>::iterator it = vec.begin(); it != vec.end(); it++) { cout << *it << " "; } cout << endl; cout << "reverse print" << endl; for (vector<int>::reverse_iterator rit = vec.rbegin(); rit != vec.rend(); rit++) { cout << *rit << " "; } cout << endl; } void use_vector_delete() { vector<int> vec(10); for (int i = 0; i < vec.size(); i++) { vec[i] = (i + 1) * (i + 1); } print_vector<int>(vec); //根据区间删除 vec.erase(vec.begin(), vec.begin() + 3); print_vector<int>(vec); //根据元素位置删除 vec.erase(vec.end() - 1); print_vector<int>(vec); //根据元素值删除 vec[2] = 6; print_vector<int>(vec); cout << "delete mem=6" << endl; for (vector<int>::iterator it = vec.begin(); it != vec.end();) { if (*it == 6) { it = vec.erase(it); } else { it++; } } print_vector<int>(vec); } void use_vector_insert() { vector<int> vec(5); for (int i = 0; i < vec.size(); i++) { vec[i] = (i + 1) * (i + 1); } print_vector<int>(vec); vec.insert(vec.begin(), 10); print_vector<int>(vec); vec.insert(vec.end(), 100); print_vector<int>(vec); } int main() { // use_vector_int1(); use_vector_insert(); // use_vector_Teacher(); return 0; }