sum to n

Author: realDuYuanChao

maths/sum_to_n.py

@@ -0,0 +1,14 @@
+def sum_to_n(n: int) -> int:
+    """
+    >>> sum_to_n(100)
+    5050
+    >>> sum_to_n(10)
+    55
+    """
+    return sum(i for i in range(1, n + 1))
+
+
+if __name__ == '__main__':
+    from doctest import testmod
+
+    testmod()