list insertion sorting code in c++

insertion sort inside the list using C++

cpp code

void insertSortList(LIST *L, int x) 
{ 
NODE *nextptr,*previus,*newptr; 
nextptr=L->head; 
previus=nextptr; 
if(nextptr==NULL) 
{ 
newptr=(NODE*) malloc(sizeof(NODE)); 
newptr->data=x; 
newptr->next=L->head; 
L->head=newptr; 
L->size++; 
return; 
} 
else if(x<L->head->data) 
{ 
newptr=(NODE*) malloc(sizeof(NODE)); 
newptr->data=x; 
newptr->next=L->head; 
L->head=newptr; 
return; 
} 
else{ 
while ((nextptr != NULL )&& ((nextptr->data) < x )) 
{ 
previus = nextptr; 
nextptr = nextptr->next; 
} 
newptr=(NODE *)malloc(sizeof(NODE)); 
newptr->data=x; 
newptr->next=nextptr; 
previus->next=newptr; 
L->size++; 
return; 
} 
} 
void deleteNode(LIST *L, int x) 
{ 
NODE *nextptr, *previus; 
nextptr = L->head; 
if (nextptr->data == x) 
{ //the head is treated separately 
L->head = nextptr->next; 
L->size--; 
free(nextptr); 
return; 
} 
else 
{ 
while (nextptr != NULL) 
{ //find x and delete it 
if (nextptr->data == x) 
{ //value found 
Previus->next =nextptr->next; 
free(nextptr); 
L->size--; 
return; 
} 
previus = nextptr; //use *previus as the previous position pointer 
nextptr = nextptr->next; 
} 
} 
}//delete