hadoop jar $HADOOP_HOME/share/hadoop/tools/lib/hadoop-streaming-*.jar \
  -files ch02-mr-intro/src/main/ruby/max_temperature_map.rb,\
ch02-mr-intro/src/main/ruby/max_temperature_reduce.rb \
  -input input/ncdc/all \
  -output output \
  -mapper ch02-mr-intro/src/main/ruby/max_temperature_map.rb \
  -combiner ch02-mr-intro/src/main/ruby/max_temperature_reduce.rb \
  -reducer ch02-mr-intro/src/main/ruby/max_temperature_reduce.rb
