Some trees were planted around the pond. Xiao Ming and Xiao Hong walked around the pond in opposite directions, counting trees while walking. Because the starting points of the two people are different, the 30th tree of Xiaoming's number is the 67th tree in Xiaohong's place, and the 77th tree of Xiaoming's number is the 67th tree in Xiaohong's place. May I ask how many trees are planted around the pool?
池塘周围栽种了一些树木，小明和小红沿相反的方向绕水池散步，边走边数树的棵树．由于两个人的出发点不同，因此小明数的第30棵在小红那里是第67棵，小明数的第77棵在小红那是第67棵．请问水池四周共栽了多少棵树？
<gadget id="calculator">30 - 7 - 7</gadget>
<output>16</output>

<gadget id="calculator">67 + 16</gadget>
<output>83</output>

<result>83</result>