All pairs shortest paths

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Input

  1. A directed graph [math]\displaystyle{ G = (V,A) }[/math]
  2. An arc length [math]\displaystyle{ l(a) \in \mathbb{R} }[/math] for each arc [math]\displaystyle{ a \in A }[/math]

Ouptut

For each pair [math]\displaystyle{ (v,w) \in A }[/math] with [math]\displaystyle{ v,w \in V }[/math], the length [math]\displaystyle{ \Delta(v,w) }[/math] of a shortest [math]\displaystyle{ (v,w) }[/math]-path in [math]\displaystyle{ G }[/math] with respect to [math]\displaystyle{ l }[/math].

Complexity

Polynomial

Known algorithms

  1. Floyd-Warshall
  2. Bellman-Ford
  3. Shortest paths by repeated squaring (varian of Bellman-Ford)