Poisson random number generator

[code]
randomsToGenerate<-20
z<-matrix(0,randomsToGenerate,1)
for(i in 1:randomsToGenerate){
    lambda<-1
    L<-exp(-lambda)
    k<-0;p<-1
        while(p>L){
        k<-k+1
        p<-p*runif(1)
        z[i]<-k-1
    }
}
[/code]