A research laboratory has 39 telescopes initially. They added 7 more telescopes in the first month and then 17 more in the second month. Twelve more telescopes arrived in the third month, followed by further add up of 18 in the fourth month. In fifth month, they got exactly the same number of telescopes as they had initially i.e. 39 telescopes and in the sixth month, they received extra 19 telescopes. How many telescopes does the research laboratory have at the end of the sixth month.