The max-cut min-flow theorem ensures that the minimum cut of a directed network is equal to the maximum throughput. And we can calculate $ S $ and $ T $, are disjoint subsets containing the source and receiver nodes of the residual graph, respectively.

What will be $ S $ and $ T $ if the maximum flow from the source to the well is equal to 0, there is no path led from $ s $ at $ t $? is $ S $ is going to be the singleton set {s} or its empty set $ phi $ and $ T $ to be the set of summits $ V $?