program main
   integer a(10)  
   integer i
   real avg 
   do i = 1, 10  
       a(i) = i * 2  
   end do  
   avg = 0  
   do i = 1, 10  
      avg = avg + a(i)  
   end do  
print *, "平均值：", avg / 10  
!习题二答案：25，24，360，11，36
end