RANDU <- function() {
    seed <<- ((2^16 + 3) * seed) %% (2^31)
    seed/(2^31)
}

y<-rep(0,300000)
seed<-45813
for (i in 1:300000){
  y[i]<-RANDU()
  }

x<-cbind(y[1:29999],y[2:30000])
plot(x)

y<-matrix(y,ncol=3,byrow=T)
z<-y[(0.5<y[,2])&(y[,2]<0.51),c(1,3)]
plot(z[,1],z[,2])