4주차 박지완 DSLR

Author: Batwan01

week4/9019_batwan01.py

@@ -1,68 +1,36 @@
-import math
+from collections import deque
 
-def double(n1, n2):
-    if n1 == 0: 
-        return -1
-    if n1 < n2:  
-        if n2 % (2 * n1) == 0:
-            log_n1 = math.log2(n2 // (2 * n1))
-            if log_n1.is_integer():
-                return int(log_n1) + 1
-        return -1
-    else: 
-        n1 = (2 * n1) % 10000 
-        if n1 == n2:
-            return 1
-        return -1
-
-def diff(n1, n2):
-    return min(abs(n1 - n2), 9999 - abs(n1 - n2) + 1)
+def dslr(start, target):
+    visited = [False] * 10000
+    queue = deque([(start, "")])
 
-def shift(n1, n2, direction):
-    a = str(n1).zfill(4)
-    b = str(n2).zfill(4)
-    count = 0
-    for _ in range(len(a)):
-        if int(a) == int(b):
-            return count
-        if direction == "L":
-            a = a[1:] + a[0]
-        else:
-            a = a[-1] + a[:-1]
-        count += 1
-    return -1
+    while queue:
+        current, commands = queue.popleft()
+        
+        if current == target:
+            return commands
+        
+        D = (2 * current) % 10000
+        if not visited[D]:
+            visited[D] = True
+            queue.append((D, commands + "D"))
+        
+        S = 9999 if current == 0 else current - 1
+        if not visited[S]:
+            visited[S] = True
+            queue.append((S, commands + "S"))
+        
+        L = (current % 1000) * 10 + current // 1000
+        if not visited[L]:
+            visited[L] = True
+            queue.append((L, commands + "L"))
+        
+        R = (current % 10) * 1000 + current // 10
+        if not visited[R]:
+            visited[R] = True
+            queue.append((R, commands + "R"))
 
 N = int(input())
 for _ in range(N):
     n1, n2 = map(int, input().split())
-    min_count = float('inf')
-    flag = None
-
-    count_double = double(n1, n2)
-    if count_double != -1 and count_double < min_count:
-        min_count = count_double
-        flag = "D"
-
-    count_diff = diff(n1, n2)
-    if count_diff < min_count:
-        min_count = count_diff
-        flag = "S"
-
-    count_L = shift(n1, n2, "L")
-    if count_L != -1 and count_L < min_count:
-        min_count = count_L
-        flag = "L"
-
-    count_R = shift(n1, n2, "R")
-    if count_R != -1 and count_R < min_count:
-        min_count = count_R
-        flag = "R"
-
-    if flag == "D":
-        print("D" * min_count)
-    elif flag == "S":
-        print("S" * min_count)
-    elif flag == "L":
-        print("L" * min_count)
-    elif flag == "R":
-        print("R" * min_count)
+    print(dslr(n1, n2))