There are 35 students in the second class of the fifth grade in a certain school, with student numbers ranging from 1 to 35. One day they went on a spring outing. Except for the monitor, the other 34 students were divided into 5 groups, and it was found that the sum of the student numbers of each group was equal; later, the 34 students were divided into 8 groups again, and it was found that the sum of the student numbers of each group was equal to equal. What is the monitor's student number?
某校五年级二班35个同学，学号分别为1～35．一天他们去春游．除了班长之外，其余34个同学分成5组，结果发现每个小组的同学学号之和都相等；后来这34个同学又重新分成8组，结果发现每个小组的同学学号之和还是相等．班长的学号是多少．
<result>30</result>