C++ Language Study 1st

C++ Language Study 1st

1. Print

#include <iostream>
using namespace std;
int main() 
{
    cout << "Hello World!" << endl;
    return 0;
}

2. Input

#include <iostream>
using namespace std;
int main()
{
    int input=0;
    cin >> input;
    cout << input << endl;
}

3-1. Reference

#include <iostream>
using namespace std;

int test(int &p)
{
    p = 3;
    return 0;
}

int main()
{
    int number = 5;
    cout << number << endl;
    test(number);
    cout << number << endl;
}

Result

5
3

3-2. Reference

#include <iostream>
using namespace std;
int main()
{
    int x;
    int &y = x;
    int &z = y;

    x=1;
    cout << x << y << z << endl;
    y=2;
    cout << x << y << z << endl;
    z=3;
    cout << x << y << z << endl;
 }

Result

111
222
333

3-3. Reference

#include <iostream>
using namespace std;
int main()
{
  int x[2][2] = {1,2,3,4};
  int (&ref)[2][2] = x;

  for(int i=0;i<2;i++)
    for(int j=0;j<2;j++)
        cout << x[i][j] << endl;
}

Result

1
2
3
4

Arrange Reference is usually don't use
* Arrange Reference size == Arrange size