complete 6571.py

zeta_python/completed/6571.py

@@ -0,0 +1,28 @@
+import sys
+import bisect
+
+input = sys.stdin.readline
+
+Mem = [1, 2, 3]
+
+
+def fib_count(a: int, b: int):
+    if b <= Mem[-1]:
+        pass
+    else:
+        while b > Mem[-1]:
+            Mem.append(Mem[-1] + Mem[-2])
+
+    right = bisect.bisect_right(Mem, b)
+    left = bisect.bisect_left(Mem, a)
+
+    return right - left
+
+
+if __name__ == "__main__":
+    while True:
+        a, b = map(int, input().split())
+        if a == b == 0:
+            break
+        else:
+            print(fib_count(a, b))