Flow network

A flow network is a graph $G=(V,E,c,s,t)$ where:

• $V$ is a set of $n$ nodes
• $E$ is a set of $m$ edges (links)
• For each $(u,v)\in E$, $c(u,v)\ge 0$ is the capacity of edge $(u,v)$ If $(u,v)\notin E$, then for convenience we define $c(u,v)=0$
• There are two distinguished nodes: source $s$ and sink $t$ where $s\ne t$