static int
count_below(tree_node *node)
{
int nleft, nright;
if (node == NULL) return 0;
nleft = count_below(node->left);
nright = count_below(node->right);
node->balance = (nleft > nright)? 1 : ((nright > nleft)? 2 : 0);
return 1 + ((nleft > nright)? nleft : nright);
}
static BOOL
read_nonrecipients_tree(tree_node **connect, FILE *f, uschar *buffer,
int buffer_size)
{
tree_node *node;
int n = Ustrlen(buffer);
BOOL right = buffer[1] == 'Y';
if (n < 5) return FALSE; /* malformed line */
buffer[n-1] = 0; /* Remove \n */
node = store_get(sizeof(tree_node) + n - 3);
*connect = node;
Ustrcpy(node->name, buffer + 3);
node->data.ptr = NULL;
if (buffer[0] == 'Y')
{
if (Ufgets(buffer, buffer_size, f) == NULL ||
!read_nonrecipients_tree(&node->left, f, buffer, buffer_size))
return FALSE;
}
else node->left = NULL;
if (right)
{
if (Ufgets(buffer, buffer_size, f) == NULL ||
!read_nonrecipients_tree(&node->right, f, buffer, buffer_size))
return FALSE;
}
else node->right = NULL;
(void) count_below(*connect);
return TRUE;
}
/*
*Perform a binary search for the threshold x, such that <= count elements are less
*x
*/
double find_threshold(int count, double t[256][256], int i_lo , int i_hi, int j_lo, int j_hi){
int i, j;
double min = 1E6, max = 0;
for(i = i_lo; i <= i_hi; i++) for(j = j_lo; j <= j_hi; j++){
if(t[i][j] < min)
min = t[i][j];
if(t[i][j] > max)
max = t[i][j];
}
double l = min - 1;
double r = max + 1;
while(l < r - 1E-5){
double x = (l+r) / 2;
int d = count_below(x, t, i_lo, i_hi, j_lo, j_hi);
if(d == count)
return x;
if(d < count)
l = x;
else
r = x;
}
printf("Problem in \"Find Threshold\"\n");
return l;
}
