just moved some files

university/exercises/fibibi.py

@@ -0,0 +1,48 @@
+def fibo(n: int, mem=None) -> int:
+    if mem is None:
+        mem = {}
+    if n <= 1:
+        return n
+    if n in mem:
+        return mem[n]
+    mem[n] = fibo(n - 1, mem) + fibo(n - 2, mem)
+    return mem[n]
+
+
+memo = {1: [1]}
+
+
+def syracuse(n):
+    if n in memo:
+        return memo[n]
+    if n % 2 == 0:
+        seq = [n] + syracuse(n // 2)
+    else:
+        seq = [n] + syracuse(3 * n + 1)
+    memo[n] = seq
+    return seq
+
+
+if __name__ == "__main__":
+    import time
+
+    n = int(input("n: "))
+    start = time.time()
+    print(fibo(n))
+    print(len(str((fibo(n)))))
+    end = time.time()
+    print(end - start)
+
+
+def fibo_fast(n: int) -> int:
+    def _fd(k: int) -> tuple[int, int]:
+        if k == 0:
+            return (0, 1)
+        a, b = _fd(k // 2)
+        c = a * ((b << 1) - a)
+        d = a * a + b * b
+        if k & 1:
+            return (d, c + d)
+        return (c, d)
+
+    return _fd(n)[0]