C++ primer plus裡的一個程式
阿新 • • 發佈:2018-12-10
#include<iostream>
#include<vector>
#include<array>//visual studio 2005不支援array
int main()
{
using namespace std;
double a1[4]={1.2,2.4,3.6,4.8};
vector<double>a2(4);
a2[0]=1.0/3.0;
a2[1]=1.0/5.0;
a2[2]=1.0/7.0;
a2[3]=1.0/9.0;
array<double,4> a3={3.74,2.72,1.62,1.41};
array<double,4> a4;
a4=a3;
cout<<"a1[2]: "<<a1[2]<<" at "<<&a1[2]<<endl;
cout<<"a2[2]: "<<a2[2]<<" at "<<&a2[2]<<endl;
cout<<"a3[2]: "<<a3[2]<<" at "<<&a3[2]<<endl;
cout<<"a4[2]: "<<a4[2]<<" at "<<&a4[2]<<endl;
a1[-2]=20.2;// a1[-2]=*(a1-2);這個之前很少注意到
cout<<"a1[-2]: "<<a1[-2]<<"at "<<&a1[-2]<<endl;
cout<<"a3[2]: "<<a3[2]<<" at "<<&a3[2]<<endl;
cout<<"a4[2]: "<<a4[2]<<" at "<<&a4[2]<<endl;
return 0;
}
#include<vector>
#include<array>//visual studio 2005不支援array
int main()
{
using namespace std;
double a1[4]={1.2,2.4,3.6,4.8};
vector<double>a2(4);
a2[0]=1.0/3.0;
a2[1]=1.0/5.0;
a2[2]=1.0/7.0;
a2[3]=1.0/9.0;
array<double,4> a3={3.74,2.72,1.62,1.41};
array<double,4> a4;
a4=a3;
cout<<"a1[2]: "<<a1[2]<<" at "<<&a1[2]<<endl;
cout<<"a2[2]: "<<a2[2]<<" at "<<&a2[2]<<endl;
cout<<"a3[2]: "<<a3[2]<<" at "<<&a3[2]<<endl;
cout<<"a4[2]: "<<a4[2]<<" at "<<&a4[2]<<endl;
a1[-2]=20.2;// a1[-2]=*(a1-2);這個之前很少注意到
cout<<"a1[-2]: "<<a1[-2]<<"at "<<&a1[-2]<<endl;
cout<<"a3[2]: "<<a3[2]<<" at "<<&a3[2]<<endl;
cout<<"a4[2]: "<<a4[2]<<" at "<<&a4[2]<<endl;
return 0;
}