N, M, S, G = gets.split.map(&:to_i)
INF=99999
ma = Array.new(N).map{Array.new(N,INF)}
ro = Array.new(N).map{Array.new(N,[INF])}
(0...M).each{|m|
    a, b, c = gets.split.map(&:to_i)
    ma[a][b]=c
    ro[a][b]=[a]
    ma[b][a]=c
    ro[b][a]=[b]
}
(0...N).each{|i|
    (0...N).each{|j|
        (0...N).each{|k|
=begin
                    if i==5 && j==6 then
                        puts
                        puts "ma[#{i}][#{j}]=#{ma[i][j]}, ro[#{i}][#{j}]=#{ro[i][j].join(' ')}"
                        puts "ma[#{i}][#{k}]=#{ma[i][k]}, ro[#{i}][#{k}]=#{ro[i][k].join(' ')}"
                        puts "ma[#{k}][#{j}]=#{ma[k][j]}, ro[#{k}][#{j}]=#{ro[k][j].join(' ')}"
                    end
=end
            if (ma[i][k] + ma[k][j] < ma[i][j])  ||
                (ma[i][j]==ma[i][k] + ma[k][j] && (ro[i][k]+ro[k][j]).join("")<ro[i][j].join("")) then
                    ma[i][j] = ma[i][k]+ma[k][j]
                    ro[i][j] = ro[i][k]+ro[k][j]
            end
        }
    }
}
puts ro[S][G].join(" ") + " " + G.to_s