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/*
File DepthFirstSearch.m
This search is a standard depth first one. At each step, the variable with the highest efficiency is selected and filled. The search backtracks when a variable has no remaining values.
It is the responsibility of the variables to implement any special heuristics like backjumping and leapfrogging.
*/
#import <appkit/appkit.h>
#import "DepthFirstSearch.h"
/* 行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行 */
#define variable(i) ([variables objectAt: i])
/* 行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行 */
@implementation DepthFirstSearch
- (BOOL) startSearch: (id) theVariables
{
variables = theVariables;
next = 0;
ok = YES;
last = nil;
count = [variables count];
return [self continue];
}
- (BOOL) continue
{
while ([NXApp getNextEvent: NX_KEYDOWNMASK
waitFor: 0
threshold: NX_MODALRESPTHRESHOLD] == NULL)
if ([self step] == NO) return NO;
return YES;
}
- (BOOL) step
{
if (ok) [self findBest];
ok = [self fill: variable(next)];
if (!ok && (next-- == 0)) return [self done];
else if (ok && (++next == count)) return [self done];
else return YES;
}
- (BOOL) done
{
[last unhilight];
return NO;
}
- (BOOL) fill: (id) variable
{
BOOL status;
[last unhilight];
[variable hilight];
status = [last = variable fillNext];
return status;
}
/* 行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行行 */
- findBest
{
float value, current;
int best, i;
id temp;
for (best = 0, value = -1.0, i = next; i < count; i++)
{
if ((current = [variable(i) efficiency]) > value)
{
value = current;
best = i;
}
}
temp = variable(next);
[variables replaceObjectAt: next with: variable(best)];
[variables replaceObjectAt: best with: temp];
return self;
}
@endThese are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.