N, M = gets.split.map(&:to_i)
@graph=Array.new(N).map{Array.new()}
@rgraph=Array.new(N).map{Array.new()}
while gets
    a,b,c=$_.split.map(&:to_i)
    @graph[a].push([b,c/100.0])
    @rgraph[b].push([a,c/100.0])
end

@memo={}
def go(n)
    if @memo[n]
        return @memo[n]
    end
    neg=1.00
    @rgraph[n].each{|pa|
        i = pa[0]
        p = pa[1]
        neg *= (1-go(i)*p)
    }
    ret = 1.00 - neg
    @memo[n] = ret
    return ret
end
@memo[0]=1
ret = go(N-1)
puts ret