fcn FloydWarshallWithPathReconstruction(dist){ // dist is munged
   V:=dist[0].len();
   next:=V.pump(List,V.pump(List,Void.copy).copy);  // VxV matrix of Void
   foreach u,v in (V,V){ if(dist[u][v]!=Void and u!=v) next[u][v] = v }
   foreach k,i,j in (V,V,V){
      a,b,c:=dist[i][j],dist[i][k],dist[k][j];
      if( (a!=Void and b!=Void and c!=Void and a>b+c) or  // Inf math
      (a==Void and b!=Void and c!=Void) ){
     dist[i][j] = b+c;
     next[i][j] = next[i][k];
      }
   }
   return(dist,next)
}
fcn path(next,u,v){
   if(Void==next[u][v]) return(T);
   path:=List(u);
   while(u!=v){ path.append(u = next[u][v]) }
   path
}
fcn printM(m){ m.pump(Console.println,rowFmt) }
fcn rowFmt(row){ ("%5s "*row.len()).fmt(row.xplode()) }