public static int generatorPoisson(double lambda){
		int x = 0;
		double q = Math.exp(-lambda);
		double s = q;
		double p = q;
		double u = generatorU();
		while(u > s){
			x++;
			p=p*lambda/x;
			s=s+p;
		}
		//System.out.println("Poisson: "+x);
		if(x==0){ //Client can't arive the exact second. Minimum is 1 second.
			x=1;
		}
		return x;
	}


	public static int generatorPoisson2(double lambda){
		int x = -1;
		double s = 1;
		double u;
		double q = Math.exp(-lambda);
		while(s>q){
			u = generatorU();
			s = s*u;
			x++;
		}
		if(x==0){ //Client can't arive the exact second. Minimum is 1 second.
			x=1;
		}
		return x;
	}