C/C++用new、delete分配回收堆中空间

int *CreateList()
 10 {
 11     int a[5];
 12     int *a = new int[5];
 13     delete[] a;
 14
 15     int a(5);
 16     int a = 5;
 17     int *a = new int(5);
 18     delete a;
 19     return a;
 20 }