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import org.apache.spark.{SparkConf, SparkContext}

/**
  * @author zoujc
  * @date 2018/11/15
  */
object topN {
	def main(args: Array[String]): Unit = {
		val conf = new SparkConf().setAppName("topN").setMaster("local[2]"
 
)
		val sc = new SparkContext(conf)
		val topNRDD = sc.textFile("C:\\Users\\ZJC\\Desktop\\wc.txt")
        		.map(_.split(" "))
				.map(x => (x(0),x(1)))
				.groupByKey()
        		.map(x =>{
			        val xx = x._1
			        val yy = x._2
			        (xx,yy.toList.sorted.reverse.take(3))
		        }
 
)
		topNRDD.foreach(println)
	}
}