From 3f68408a3f3ab54de4f87c1fd97724f5eb94eff9 Mon Sep 17 00:00:00 2001
From: Lars Wirzenius <liw@liw.fi>
Date: Sat, 29 May 2021 21:09:18 +0300
Subject: refactor: make server handle also min, not just max

Sponsored-by: author
---
 server.py | 48 ++++++++++++++++++++++++++++++++----------------
 1 file changed, 32 insertions(+), 16 deletions(-)

diff --git a/server.py b/server.py
index 0479d1d..0d676db 100755
--- a/server.py
+++ b/server.py
@@ -4,28 +4,44 @@ import bottle
 import random
 
 
-class Max:
+def max(answer):
+    return answer
+
+
+def min(answer):
+    return not answer
+
+
+class Find:
     def __init__(self):
-        self.new(0)
+        self.reset()
+
+    def reset(self):
+        self._algo = None
+        self._count = None
+        self._result = 0
+        self._pos = 0
+        self._rid = None
+
+    def new(self, algo, count):
+        assert count > 0
 
-    def new(self, count):
         if count == 1:
             # List has length 1: we know the answer.
             return self.done(0)
 
+        self.reset()
+        self._algo = algo
         self._count = count
-        self._result = 0
-        self._pos = 0
-        self._rid = None
         return self.next(self._result)
 
     def decide(self, answer, rid):
         assert rid == self._rid
-        if answer:
-            # left < right: use previous "right" item
+        if self._algo(answer):
+            # use previous "right" item in comparison
             return self.next(self._pos)
         else:
-            # left >= right: use current best result
+            # use previous result
             return self.next(self._result)
 
     def next(self, new_result):
@@ -43,7 +59,6 @@ class Max:
 
     def compare(self, left, right):
         self._rid = random.randint(1, 2 ** 30)
-        self._pos = right
         return {
             "type": "compare",
             "left": left,
@@ -55,7 +70,7 @@ class Max:
         return {"type": "done", "result": n}
 
 
-session = Max()
+session = Find()
 
 
 @bottle.post("/")
@@ -63,13 +78,14 @@ def root():
     msg = bottle.request.json
     print("request", msg)
     msg_type = msg.get("type")
-    assert msg_type in ("compute_max", "comp_result")
     if msg_type == "compute_max":
-        n = msg["length"]
-        assert n > 0
-        o = session.new(n)
-    else:
+        o = session.new(max, msg["length"])
+    elif msg_type == "compute_min":
+        o = session.new(min, msg["length"])
+    elif msg_type == "comp_result":
         o = session.decide(msg["answer"], msg["request_id"])
+    else:
+        assert False
 
     print("result", o, session._pos)
     bottle.response.content_type = "application/json"
-- 
cgit v1.2.1