網絡流量：對或錯

Question

In a directed graph with at most one edge between each pair of vertices, if we 
replace each directed edge by an undirected edge, the maximum flow 
value remains unchanged. 

爲什麼它是假的？

爲什麼以及如何改變流量？

謝謝。

Answer 1

因爲邊緣可能是錯誤的。有更多有趣的情況，但考慮這個微不足道的：

S <- T 

無論邊緣的容量如何，流量爲零。如果您將其設爲無向，流量將取決於邊緣的容量。