typo
diff --git a/sim.py b/sim.py
--- a/sim.py
+++ b/sim.py
@@ -118,7 +118,7 @@ def fold(net, num=10):
def linklengths(net):
- """calculate the lengthsof all links"""
+ """calculate the lengths of all links"""
lengths = []
for node, targets in net.items():
for t in targets: