C++ code segments

一.function alias invocation(引用)

#include <iostream>
using namespace std;
void aliasFun(int &, int &);
int main()
{
int num = 10;
cout << "Num = " << num << endl;
int &i = num;
i = 20;
cout << "i = " << i << endl;
cout << "Num = " << num << endl;
int x = 200;
int y = 300;
aliasFun(x,y);
cout << "x = " << x << ", " << "y = " << y << endl;
return 0;
}
void aliasFun(int &a,int &b)
{
a = 4;
b = 10;
}

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二.type cast
#include <iostream>
using namespace std;
int main(int argc, char **argv)
{
double d = 3.1415926;
int i1 = static_cast<int>(d);
int i2 = (int)d; // old method
cout << "i1 = " << i1 << endl;
cout << "i2 = " << i2 << endl;
return 0;
}

-----------------------------------------

3.Array definition

int a[4]; // definition
int a[4] = {1,10,2,4} // defination and initialization

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4.pointer
int a = 10;
int *p = &a;
int *p = new int;
int *p = new int[10]; //dynamic allocate array
delete p;
delete [] p;

void swap(int *num1,int *num2)
{
int temp = *num1;
*num1 = *num2;
*num2 = temp;
}

int main(){
int x = 10;
int y = 20;
swap(&x,&y);
}

-------------------------------

5.character && string
char *p = "hello very good";
while(p != "\0")
{
cout << *p++;
}

------------
char str[10] = "hello!";
char *p = str;
for(int i=0;i<6;i++)
{
cout << *(p+i);
}