37 lines
946 B
Go
37 lines
946 B
Go
package main
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//
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// a word-count application "plugin" for MapReduce.
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//
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// go build -buildmode=plugin wc_long.go
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//
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import (
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"strconv"
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"strings"
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"time"
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"6.5840/mr"
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)
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// The map function is called once for each file of input.
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// This map function just returns 1 for each file
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func Map(filename string, contents string) []mr.KeyValue {
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kva := []mr.KeyValue{}
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kva = append(kva, mr.KeyValue{filename, "1"})
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return kva
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}
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// The reduce function is called once for each key generated by the
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// map tasks, with a list of all the values created for that key by
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// any map task.
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func Reduce(key string, values []string) string {
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// some reduce tasks sleep for a long time; potentially seeing if
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// a worker will accidentally exit early
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if strings.Contains(key, "sherlock") || strings.Contains(key, "tom") {
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time.Sleep(time.Duration(3 * time.Second))
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}
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// return the number of occurrences of this file.
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return strconv.Itoa(len(values))
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}
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