Microsoft Visual Studio 2010出现LNK1120问题

我用的是Micro Visual Studio 2010 ,编译时出现MSVCRTD.lib(crtexe.obj) : error LNK2019: unresolved external symbol _main referenced in function ___tmainCRTStartup
1>D:\Program Files\Microsoft Visual Studio 10.0\myproject\test6gai\Debug\test6gai.exe : fatal error LNK1120: 1 unresolved externals
请问高手如何解决？程序应该不会错，是从C++ Primer上照抄下来的。有人说改project->setting->link.可是2010没有这个选项啊。

#include<iostream>
#include<vector>
using namespace std;
int mian()
{
    int ival;
    vector<int> ivec;
    cout<<"enter numbers(Ctrl+z to end)"<<endl;
    while(cin>>ival)
    {
        ivec.push_back(ival);
    }
    if(ivec.size()==0)
    {
        cout<<"no element"<<endl;
        return -1;
    }
    cout<<"sum of each pair of adjacent elements in the vector:"<<endl;
    vector<int>::size_type cnt=0;
    for(vector<int>::iterator iter=ivec.begin();iter<ivec.end()-1;iter=iter+2)
    {
        cout<<*iter+*(iter+1)<<endl;
        ++cnt;
        if(cnt%6==0)
            cout<<endl;
    }
    if(ivec.size()%2!=0)
    {
            cout<<"最后一个元素没参加计算,这个值为"<<*(ivec.end()-1)<<endl;
    }
    return 0;
}