The worst-case running time for Floyd's algorithm is easily determined.
Creating and initializing the distance matrix is
(lines 6-9).
Transferring the weights from the input graph to the distance matrix
requires
time if adjacency lists are used,
and
time when an adjacency matrix is used to represent
the input graph (lines 11-18).
The running time for the three nested loops
is in the worst case.
Finally, constructing the result graph
and transferring the entries from the distance matrix
to the result requires
time.
As a result, the worst-case running time of Floyd's algorithm
is
.