Provide avectorized solution that replaces the entire expression in these function by aone line expression that does not use loop. You can assume x is a numeric vector and valis a single numeric value.

a)     val.positions<-function(x,val)

{

          val.pos<-NULL

          for(i in 1:length(x)  )

          if (x==val) val.pos<-c(val.pos,i)

          val.pos

     }

b)      monotonic<-function(x)

{     monotonic.increasing<-TRUE

      monotonic.decreasing<-TRUE

       for(iin 2:length(x)) if(x-x[i-1]<0) monotonic.increasing<-FALSE

             for(i in 2:length(x)) if(x-x[i-1]>0)monotonic.decreasing<-FALSE

             monotonic.increasing | monotonic.decreasing

     }

这道题完全没有头绪，哪位热心的前辈能帮忙解答一下或者给一些思路，万分感谢。