Following is the algorithm to find all pairs shortest path in a weighted directed graph, where W[][] is adjacency matrix with weights.

Floyd(W[1..n, 1..n]) //Implements Floyd's algorithm for the all-pairs shortest-paths problem //Input: The weight matrix W of a graph with no negative-length cycle //Output: The distance matrix of the shortest paths' lengths D < W /is not necessary if W can be overwritten for k < 1 to n do for i < 1 to n do for j + 1to n do D[i, il < min{D[i, j]. D[i, K] + D[k, jl) return D