问答题

[函数5-1]
bool SearchBtree(BTreeNode* root, ElemKeyType akey, BTreeNode **ptr)
{
int lw, hi, mid;
BTreeNode*p = root;
*ptr = NULL;
while ( p ) {
1w = 1; hi= (1) ;
while (1w ＜= hi) {
mid = (1w + hi)/2;
if (p -＞ K[mid] == akey) {
*ptr = p;
return TRUE;
}
else
if ( (2) )
hi=mid - 1;
else
1w = mid + 1;
}
*ptr = p;
p = (3) ;
}
return FALSE;
}