The students went to the botanical garden. There were 30 people who visited the chrysanthemum garden, 35 people who visited the rose garden, and 19 people who visited both gardens. How many people went to the botanical garden?
同学们到植物园游玩，参观菊花园的有30人，参观玫瑰园的有35人，两个园都参加的有19人，去植物园游玩的一共有多少人．
<gadget id="calculator">35 - 19</gadget>
<output>16</output>

<gadget id="calculator">30 + 16</gadget>
<output>46</output>

<result>46</result>