p = new int; => p=(int *) malloc(sizeof(int));
delete p; => free(p);
p_array = new int[array_size];
delete[] p_array;
可以赋初值(执行构造函数)
p = new int(5);
p = new int; => p=(int *) malloc(sizeof(int));
delete p; => free(p);
p_array = new int[array_size];
delete[] p_array;
可以赋初值(执行构造函数)
p = new int(5);