[중요] C++ 0.07 - new, delete

C vs C++

// C
int *p = (int *)malloc(sizeof(int) * N);

for (int i = 0; i < N; i++)
  p[i] = i;
  
free(p);


// C++
int *p = new int[N]; 
// or int &p = new int[N];

for (int i = 0; i < N; i++)
  p[i] = i;

delete[] p;

 

N : 할당할 배열 개수.

 

 

Example

---

int *p = new int;                  // pi points to unintialized int
int *pi = new int(7);              // which pi points has value 7
string *ps = new string("hello")   // ps points "hello"

int *pia = new int[7];             // block of seven unintialized ints
int *pia = new int[7]();           // block of seven ints value intialized to 0

string *psa = new string[5];              // block of 5 empty strings
string *psa = new string[5]();            // block of 5 empty strings
int *pia = new int[5]{0,1,2,3,4};         // block of 5 ints intialized
string *psa = new string[2]{"a", "the"    // block of 2 strings intialized

delete pi;
delete[] pia;