我正在尝试从克里斯·松的“学习计划”书中回答以下问题：
Leap years. Write a program that asks for a starting year and an ending year and then puts all the leap years between them (and including them,if they are also leap years). Leap years are years divisible by 4 (like 1984 and 2004). However,years divisible by 100 are not leap years (such as 1800 and 1900) unless they are also divisible by 400 (such as 1600 and 2000,which were in fact leap years). What a mess!
leap_year.rb：12：in’：没有将Fixnum隐式转换为String(TypeError)
从leap_year.rb：12：在’
这是我的代码：
#leap years
puts 'What is the starting year?'
starting_year = gets.chomp
puts 'What is the ending year?'
ending_year = gets.chomp
while starting_year <= ending_year
if starting_year%4 == 0 && (starting_year%100 != 0 && starting_year%400 == 0)
puts starting_year
end
starting_year+=1
end