swap
#include <iostream>
#include <vector>
using namespace std;
int swap1(int* px,int* py){
int z=*px;
*px=*py;
*py=z;
return 0;
}
int swap2(int &ix,int &iy){
int z=ix;
ix=iy;
iy=z;
return 0;
}
int main(int argc, char* argv[])
{
int x,y;
cout<<"intput x and y:"<<endl;
cin>>x;
cin>>y;
swap1(&x,&y);
cout<<"swap1:"<<x<<","<<y<<endl;
swap2(x,y);
cout<<"swap2:"<<x<<","<<y<<endl;
}
-------------------------------------------------------
seq
#include <iostream>
#include <vector>
using namespace std;
bool fibon_elem(int iPos, int &iElem)
{
int n2 = 1, n1 = 1;
if (iPos <= 0 || iPos >= 1024)
{
iElem = 0; return false;
}
iElem = 1;
for (int iX = 3; iX <= iPos; iX++)
{
iElem = n2 + n1;
n2 = n1;
n1 = iElem;
}
return true;
}
int fibon_elem(int iPos)
{
int n2 = 1, n1 = 1;
int iElem = 1;
for (int iX = 3; iX <= iPos; iX++)
{
iElem = n2 + n1;
n2 = n1;
n1 = iElem;
}
return iElem;
}
vector<int> fibon_seq(int iLength)
{
if (iLength <= 0 || iLength >= 1024)
{
cerr <<"Length"<<iLength<<"not supported, reset to 8"<<endl;
iLength = 8;
}
vector<int> Elems( iLength );
for (int iX = 0; iX < iLength; iX++){
if (iX == 0 || iX == 1)
{
Elems[iX] = 1;
}
else
{
Elems[iX] = Elems[iX-1] + Elems[iX-2];
}
}
return Elems;
}
int main(int argc, char* argv[])
{
int x,y;
cout<<"please input a num(from 0-1024):";
cin>>x;
cout<<"first result:"<<fibon_elem(x);
if(fibon_elem(x,y))
cout<<endl<<"second result:"<<y;
else
cout<<endl<<"second result:error";
vector<int> Elems=fibon_seq(x);
cout<<endl<<"third result:";
for(int i=0;i<Elems.size();i++)
cout<<Elems[i]<<",";
cout<<endl;
return 0;
}
--------------------------------------------
根据main的参数选择函数
int main(int argc, char* argv[])
{
if(argc!=2){
cout<<"input error,like guo1.exe c/e"<<endl;
return 0;
}
if(strcmp(argv[1],"c")==0)
cout<<"c";
else
cout<<"e";
}
类
-----------------------
#include <iostream>
#include <vector>
using namespace std;
class X
{
public:
int mf1(){cout<<"hello";return 0;};
int mf2() { return mf3(); }
private:
int mf3(){cout<<"hello";return 0;};
} x;
void main()
{
x.mf1(); //yes
x.mf2();
//x.mf3(); //Error! Private member can’t be accessed out of the class
}
---------------y
#include <iostream>
#include <vector>
using namespace std;
class Y
{
public:
int _m1;
int get_m2() { return _m2;}
void set_m2(int x) { _m2 = x;}
private:
int _m2;
} y;
void main()
{
y._m1++; //Not suggested! Direct access data members
cout<<y._m1;
y.set_m2(1); //Suggested! The data member is accessed under control
cout<<y.get_m2();
}
