修改元素示例

#include <iostream>#include <vector>int main(int argc,char *argv[]){    std::vector <int> int_vec;    int_vec.push_back(1);    int_vec.push_back(2);    int_vec.push_back(3);    int nSize=int_vec.size();    std::cout << "通过数组修改：" << std::endl;    int_vec[1]=5;    for(int i=0;i<nSize;i++)    {        std::cout << int_vec[i] << "\t" ;    }    std::cout << std::endl;    std::cout << "通过引用修改 "  << std::endl;    int &value=int_vec[1]=40;    for(int i=0;i<nSize;i++)    {        int & value=int_vec[i];        std::cout << value << "\t";    }    std::cout << std::endl;    std::cout << "通过迭代器修改 " << std::endl;    std::vector<int>::iterator int_vec_iter=int_vec.begin()+1;    *int_vec_iter=20;    for(int i=0;i<nSize;i++)    {        std::cout << int_vec[i] << "\t";    }    std::cout << std::endl;    return 0;}