min and max operations on matrix

Folks,

I've got a matrix x as follows:

x <- matrix(c(1,2,3,5,3,4,3,2,1), ncol = 3, byrow = TRUE)
x

[,1] [,2] [,3]
[1,]    1    2    3
[2,]    5    3    4
[3,]    3    2    1


In each row of x, I want to replace the minimum value by -1, the maximum
value by +1 and all other values by 0.

So in the above case I want to end up as follows:

     [,1] [,2] [,3]
[1,]   -1    0    1
[2,]    1   -1    0
[3,]    1    0   -1

I tried the following, which seems to work:

t(apply(x, 1, function(y) {z <- numeric(NROW(y)); z[which.min(y)] <-

-1; z[which.max(y)]<- 1; z})) 

Is there a neater way to do this?

Thanks,

Murali