练习3.23

/*************************************************************************    > File Name: 3_23.cpp    > Author:     > Mail:     > Created Time: Sun 09 Apr 2017 07:18:58 PM CST ************************************************************************/#include<iostream>#include<vector>using namespace std;int main(){    vector<int> ivec;    for(int i = 0; i < 10; ++i)    {        ivec.push_back(i*i+3);        cout<<i*i+3<<" ";    }    cout<<endl;    for(auto it = ivec.begin(); it != ivec.end(); ++it)    {        *it = (*it) * 2;        cout<<*it<<" ";    }    cout<<endl;    return 0;}