#include <iostream>
#include <vector>
#include <algorithm>
#include <cstdlib>
using namespace std;
typedef vector<int> INTVECTOR;
int main(void)
{
vector<int> num; // STL中的vector容器
int element;
// 從標(biāo)準(zhǔn)輸入設(shè)備讀入整數(shù),
// 直到輸入的是非整型數(shù)據(jù)為止
while (cin >> element) //ctrl+Z 結(jié)束輸入
num.push_back(element);
// STL中的排序算法
sort(num.begin(), num.end());
// 將排序結(jié)果輸出到標(biāo)準(zhǔn)輸出設(shè)備
for (int i = 0; i < num.size(); i ++)
cout << num[i] << " ";
cout<<endl;
//vec1對(duì)象初始為空
INTVECTOR vec1;
//vec2對(duì)象最初有10個(gè)值為6的元素
INTVECTOR vec2(10,6);
//vec3對(duì)象最初有3個(gè)值為6的元素
INTVECTOR vec3(vec2.begin(),vec2.begin()+3);
//聲明一個(gè)名為i的雙向迭代器
INTVECTOR::iterator i;
//從前向后顯示vec1中的數(shù)據(jù)
cout<<"vec1.begin()--vec1.end():"<<endl;
for (i =vec1.begin(); i !=vec1.end(); ++i)
cout << *i << " ";
cout << endl;
//從前向后顯示vec2中的數(shù)據(jù)
cout<<"vec2.begin()--vec2.end():"<<endl;
for (i =vec2.begin(); i !=vec2.end(); ++i)
cout << *i << " ";
cout << endl;
//從前向后顯示vec3中的數(shù)據(jù)
cout<<"vec3.begin()--vec3.end():"<<endl;
for (i =vec3.begin(); i !=vec3.end(); ++i)
cout << *i << " ";
cout << endl;
//測(cè)試添加和插入成員函數(shù)
vec1.push_back(2);
vec1.push_back(4);
vec1.insert(vec1.begin()+1,5); //在第一個(gè)位置后插入5
vec1.insert(vec1.begin()+1,vec3.begin(),vec3.end());//在第一個(gè)位置后插入ve3開(kāi)始到結(jié)束的數(shù)字
cout<<"push() and insert():" <<endl;
for (i =vec1.begin(); i !=vec1.end(); ++i)
cout << *i << " ";
cout << endl;
//測(cè)試賦值成員函數(shù)
vec2.assign(8,1);//重新給vec2賦了8個(gè)值1
cout<<"vec2.assign(8,1):" <<endl;
for (i =vec2.begin(); i !=vec2.end(); ++i)
cout << *i << " ";
cout << endl;
//測(cè)試引用類函數(shù)
cout<<"vec1.front()="<<vec1.front()<<endl;
cout<<"vec1.back()="<<vec1.back()<<endl;
cout<<"vec1.at(4)="<<vec1.at(4)<<endl;
cout<<"vec1[4]="<<vec1[4]<<endl;
//測(cè)試移出和刪除
vec1.pop_back();//最高位前移一位(去掉最高位)
cout<<"vec1.pop_back():" <<endl;
for (i =vec1.begin(); i !=vec1.end(); ++i)
cout << *i << " ";
cout << endl;
vec1.erase(vec1.begin()+1,vec1.end()-2);//清除 vec1.begin()+1到vec1.end()-2
cout<<"vec1.erase():" <<endl;
for (i =vec1.begin(); i !=vec1.end(); ++i)
cout << *i << " ";
cout << endl;
//顯示序列的狀態(tài)信息
cout<<"vec1.capacity(): "<<vec1.capacity()<<endl; //capacity() 告訴你最多添加多少個(gè)元素才會(huì)導(dǎo)致容器重分配內(nèi)存
cout<<"vec1.max_size(): "<<vec1.max_size()<<endl;
cout<<"vec1.size(): "<<vec1.size()<<endl; //size() 是告訴你容器當(dāng)中目前實(shí)際有多少個(gè)元素
cout<<"vec1.empty(): "<<vec1.empty()<<endl;
//vector序列容器的運(yùn)算
cout<<"vec1==vec3: "<<(vec1==vec3)<<endl; //相等返回1,不相等返回0
cout<<"vec1<=vec3: "<<(vec1<=vec3)<<endl; //小于等于返回1,否則返回0
system("pause");
return 0;
}
*
Vector: 它就是數(shù)組的一個(gè)泛化推廣, 等同于數(shù)組,它擁有一段連續(xù)的內(nèi)存空間,并且起始地址不變,
優(yōu)點(diǎn):1)很好的支持隨機(jī)存取,即[]操作符,查詢操作高效
缺點(diǎn):1)插入/刪除會(huì)造成內(nèi)存塊的拷貝,效率較低,(尾部元素除外)
2)內(nèi)存空間不夠時(shí),需要重新申請(qǐng)一塊足夠大的內(nèi)存并進(jìn)行內(nèi)存的拷貝,大大影響了vector的效率
*/
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
void printVector(vector<int> v1)
{
//使用下標(biāo)方式
//for (unsigned int i = 0; i < v1.size(); i++)
//{
// cout<<"v1["<<i<<"] = "<<v1[i]<<endl;
//}
//使用迭代器
//vector<int>::iterator iter;
//for (iter = v1.begin(); iter != v1.end(); iter++)
//{
// //cout<<"v1["<<iter-v1.begin()<<"] = "<<*iter<<endl;
// cout<<"v1["<<iter-v1.begin()<<"]"<<"="<<*iter<<", ";
//}
//cout<<endl;
//使用迭代器指針
//vector<int>::iterator *pIter; //Error,迭代器指針需要分配內(nèi)存才能使用,
//或者通俗的說(shuō)pIter未實(shí)現(xiàn)時(shí),*pIter是不確定的,運(yùn)行時(shí)對(duì)其賦值必須會(huì)發(fā)生異常
vector<int>::iterator *pIter = new vector<int>::iterator;
if(NULL == pIter)
{
return;
}
for(*pIter = v1.begin(); *pIter != v1.end(); (*pIter)++) //此處若寫(xiě)成*pIter++是不對(duì)的,因?yàn)?+優(yōu)化級(jí)別較高
{
cout<<**pIter<<", ";
}
if (NULL != pIter)
{
delete pIter;
pIter = NULL;
}
cout<<endl;
}
void reversePrintVector(vector<int> vec)
{
vector<int>::reverse_iterator revIter;
for (revIter = vec.rbegin(); revIter != vec.rend(); revIter++)
{
cout<<"v["<<revIter-vec.rbegin()<<"]="<<*revIter<<", ";
}
cout<<endl;
}
int main()
{
//創(chuàng)建
vector<int> v1; //創(chuàng)建空的vector對(duì)象
vector<int> v2(10); //創(chuàng)建具有10個(gè)元素的vector對(duì)象
vector<double> v3(10, 9.1); //創(chuàng)建具有10個(gè)元素的vector對(duì)象,每個(gè)元素的值為9.1
vector<double> v4(v3); //通過(guò)拷貝一個(gè)V3對(duì)象的各個(gè)元素值,創(chuàng)建一個(gè)新的vector對(duì)象
int iArray[] = {11, 13 , 19, 23, 27};
vector<int> v(iArray, iArray + 5);//通過(guò)拷貝迭代器區(qū)間[first, end)的元素值,創(chuàng)建新的vector對(duì)象
//初始化----用push_back,在容器的尾端插入新元素
v1.push_back(3);
v1.push_back(10);
v1.push_back(19);
//遍歷訪問(wèn):1-下標(biāo)方式(略)
//遍歷訪問(wèn)之2:迭代器方式, 建議使用此方式并熟練應(yīng)用之
cout<<"printVector(v1): "<<endl;
printVector(v1);
//反向遍歷之迭代器方式
cout<<"reversePrintVector(v1):"<<endl;
reversePrintVector(v1);
//插入元素:用insert(&pos, elem)
cout<<"v1.insert(v1.begin() + 1, 100): "<<endl;
v1.insert(v1.begin() + 1, 100);
printVector(v1);
//刪除元素: 尾部元素刪除用pop_back();單個(gè)元素刪除用erase(&pos);
//[first, last)區(qū)間元素刪除用erase(&first, &last); 整體刪除用clear();
cout<<"v1.erase(v1.begin() + 1): "<<endl;
v1.erase(v1.begin() + 1);
printVector(v1);
cout<<"v1.pop_back():"<<endl;
v1.pop_back();
printVector(v1);
//查找函數(shù):由外部算法提供
vector<int>::iterator iter;
cout<<"find(v1.begin(), v1.end(), 2) = "<<endl;
iter = find(v1.begin(), v1.end(), 10);
if (iter != v1.end())
cout<<"find "<<*iter<<" at index: "<<iter-v1.begin()<<endl;
else
cout<<"not find"<<endl;
cout<<"v1.empty() = "<<v1.empty()<<endl;
cout<<"其它:\nv1.empty() = "<<v1.empty()<<", v1.size() = "<<v1.size()<<", v1.max_size() =(hex)"<<hex<<v1.max_size()<<endl;
cout<<"head-elem="<<dec<<v1.front()<<endl;
cout<<"tail-elem="<<v1.back()<<endl;
//清空
cout<<"v1.clear() "<<endl;
v1.clear();
cout<<"v1.size() = "<<v1.size()<<", v1.empty()="<<v1.empty()<<endl;
}
/**/////////////////////////////////////運(yùn)行結(jié)果////////////////////////////////////////////////////////printVector(v1):
3, 10, 19,
reversePrintVector(v1):
v[0]=19, v[1]=10, v[2]=3,
v1.insert(v1.begin() + 1, 100):
3, 100, 10, 19,
v1.erase(v1.begin() + 1):
3, 10, 19,
v1.pop_back():
3, 10,
find(v1.begin(), v1.end(), 2) =
find 10 at index: 1
v1.empty() = 0
其它:
v1.empty() = 0, v1.size() = 2, v1.max_size() =(hex)3fffffff
head-elem=3
tail-elem=10
v1.clear()
v1.size() = 0, v1.empty()=1