Remove unnecessary else statement (#7759)

* Remove unnecessary else statement

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: AlexandreVelloso

maths/karatsuba.py

@@ -10,18 +10,18 @@ def karatsuba(a, b):
     """
     if len(str(a)) == 1 or len(str(b)) == 1:
         return a * b
-    else:
-        m1 = max(len(str(a)), len(str(b)))
-        m2 = m1 // 2
 
-        a1, a2 = divmod(a, 10**m2)
-        b1, b2 = divmod(b, 10**m2)
+    m1 = max(len(str(a)), len(str(b)))
+    m2 = m1 // 2
 
-        x = karatsuba(a2, b2)
-        y = karatsuba((a1 + a2), (b1 + b2))
-        z = karatsuba(a1, b1)
+    a1, a2 = divmod(a, 10**m2)
+    b1, b2 = divmod(b, 10**m2)
 
-        return (z * 10 ** (2 * m2)) + ((y - z - x) * 10 ** (m2)) + (x)
+    x = karatsuba(a2, b2)
+    y = karatsuba((a1 + a2), (b1 + b2))
+    z = karatsuba(a1, b1)
+
+    return (z * 10 ** (2 * m2)) + ((y - z - x) * 10 ** (m2)) + (x)
 
 
 def main():