vector练习

#include <iostream>
#include <vector>
#include <stdio.h>
#include <algorithm>
using namespace std;

//true不交换 false交换，sort默认是升序。此程序为降序
template <class T>
bool cmp(const T x,const T y)
{
	if (x>y) return 1;
	else return 0;
}
int main()
{
	vector<int>vecm;
	vecm.push_back(3);
	vecm.push_back(4);
	vecm.push_back(5);
	vecm.push_back(6);
	vecm.push_back(7);
	vecm.insert(vecm.begin()+2,100);
	vector <int>::iterator it;
	for (it=vecm.begin();it!=vecm.end();++it)
	{
		cout<<*it<<endl;
	}
	vector <int>::reverse_iterator ri;
	cout<<"============反向输出==============="<<endl;
	for (ri=vecm.rbegin();ri!=vecm.rend();++ri)
	{
		cout<<*ri<<endl;
	}
	vecm.erase(vecm.begin()+2);
	cout<<"============删除第二个==============="<<endl;
	for (it=vecm.begin();it!=vecm.end();++it)
	{
		cout<<*it<<endl;
	}
	sort(vecm.begin(),vecm.end(),cmp<int>);
	cout<<"============降序排列========"<<endl;
	for (it=vecm.begin();it!=vecm.end();++it)
	{
		cout<<*it<<endl;
	}
	cout<<"============vector的最大值====="<<endl;

	cout<<vecm.max_size()<<endl;
	cout<<"============输出某一个值====="<<endl;
	cout<<vecm.at(2)<<endl;
	cout<<"============改变第3个元素======="<<endl;
	vecm.at(2)=1000;
	cout<<vecm.at(2)<<endl;
	cout<<"============所有操作完成======="<<endl;
	for (int i=0;i<vecm.size();i++)
	{
		cout<<vecm.at(i)<<endl;
	}


	return 0;
}