function Z1 = normal_RV(num)

for i=1:num,
	while(1)
		n=1;
		Y_1 = exponential_RV(rand);
		U_2 = rand;
		if(U_2 < (exp(-0.5*(Y_1-1)^2)))
			Z_1(i)=Y_1;
			break;
		else
			n=n+1;
		end;
	end;

	U_3 = rand;
	if(U_3 <0.5),
		Z1(i) = Z_1(i);
	else
		Z1(i) = -Z_1(i);
	end;
end;