MapReduce ----倒排索引

分别建立三个文件：

file1txt

file2.txt

file3.txt

文件内容分别是：

MapReduce is simple

和

MapReduce is powerful is simple

和

Hello MapReduce bye MapReduce

 1 import java.io.IOException;
 2 import java.util.StringTokenizer;
 3 import org.apache.hadoop.conf.Configuration;
 4 import org.apache.hadoop.fs.Path;
 5 import org.apache.hadoop.io.Text;
 6 import org.apache.hadoop.mapreduce.Job;
 7 import org.apache.hadoop.mapreduce.Mapper;
 8 import org.apache.hadoop.mapreduce.Reducer;
 9 import org.apache.hadoop.mapreduce.lib.input.FileSplit;
10 import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
11 import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
12 
13 public class InvertedIndex{
14     private static class Map extends Mapper<Object, Text, Text, Text>{
15         private Text keyInfo =new Text(); //存单词与uri
16         private Text valueInfo =new Text(); //存词频
17         private FileSplit split;   //存储split对象
18         @Override
19         protected void map(Object key, Text value, Mapper<Object, Text, Text, Text>.Context context)
20                 throws IOException, InterruptedException {
21             // TODO Auto-generated method stub
22             split=(FileSplit) context.getInputSplit();
23             StringTokenizer itr=new StringTokenizer(value.toString());
24             while (itr.hasMoreTokens()) {
25                 int splitIndex=split.getPath().toString().indexOf("file");
26                 keyInfo.set(itr.nextToken()+":"+split.getPath().toString().substring(splitIndex));
27                 valueInfo.set("1");
28                 context.write(keyInfo, valueInfo);
29             }
30         }
31     }
32     
33     public static class Combine extends Reducer<Text, Text, Text, Text>{ //相同的key，value累加
34         private Text info=new Text();
35         @Override
36         protected void reduce(Text key, Iterable<Text> values, Reducer<Text, Text, Text, Text>.Context context)
37                 throws IOException, InterruptedException {
38             // TODO Auto-generated method stub
39             int sum=0;
40             for(Text value:values){
41                 sum+=Integer.parseInt(value.toString());
42             }
43             int splitIndex=key.toString().indexOf(":");
44             info.set(key.toString().substring(splitIndex+1)+":"+sum); //与下一行顺序不能调换
45             key.set(key.toString().substring(0, splitIndex));
46             context.write(key, info);
47         }
48     }
49     public static class Reduce extends Reducer<Text, Text, Text, Text>{
50         private Text result=new Text();
51         @Override
52         protected void reduce(Text key, Iterable<Text> values, Reducer<Text, Text, Text, Text>.Context context)
53                 throws IOException, InterruptedException {
54             // TODO Auto-generated method stub
55             String file=new String();
56             for(Text value:values){
57                 file+=value.toString()+";";
58             }
59             result.set(file);
60             context.write(key, result);
61         }
62     }
63     public static void main(String[] args) throws IOException, ClassNotFoundException, InterruptedException {
64          Configuration conf=new Configuration();
65          @SuppressWarnings("deprecation")
66         Job job=new Job(conf,"invertedIndex");
67          job.setJarByClass(InvertedIndex.class);
68          job.setMapperClass(Map.class);
69          job.setCombinerClass(Combine.class);
70          job.setReducerClass(Reduce.class);
71          job.setMapOutputKeyClass(Text.class);
72          job.setMapOutputValueClass(Text.class);
73          job.setOutputKeyClass(Text.class);
74          job.setOutputValueClass(Text.class);         
75          FileInputFormat.setInputPaths(job, new Path(args[0]));
76          FileOutputFormat.setOutputPath(job, new Path(args[1]));
77           System.exit(job.waitForCompletion(true)?0:1);
78     }
79 }

  1 2017-03-15 22:16:27,071 WARN [org.apache.hadoop.util.NativeCodeLoader] - Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
  2 2017-03-15 22:16:27,748 INFO [org.apache.hadoop.conf.Configuration.deprecation] - session.id is deprecated. Instead, use dfs.metrics.session-id
  3 2017-03-15 22:16:27,749 INFO [org.apache.hadoop.metrics.jvm.JvmMetrics] - Initializing JVM Metrics with processName=JobTracker, sessionId=
  4 2017-03-15 22:16:28,058 WARN [org.apache.hadoop.mapreduce.JobResourceUploader] - Hadoop command-line option parsing not performed. Implement the Tool interface and execute your application with ToolRunner to remedy this.
  5 2017-03-15 22:16:28,061 WARN [org.apache.hadoop.mapreduce.JobResourceUploader] - No job jar file set.  User classes may not be found. See Job or Job#setJar(String).
  6 2017-03-15 22:16:28,124 INFO [org.apache.hadoop.mapreduce.lib.input.FileInputFormat] - Total input paths to process : 3
  7 2017-03-15 22:16:28,171 INFO [org.apache.hadoop.mapreduce.JobSubmitter] - number of splits:3
  8 2017-03-15 22:16:28,289 INFO [org.apache.hadoop.mapreduce.JobSubmitter] - Submitting tokens for job: job_local1466554694_0001
  9 2017-03-15 22:16:28,463 INFO [org.apache.hadoop.mapreduce.Job] - The url to track the job: http://localhost:8080/
 10 2017-03-15 22:16:28,468 INFO [org.apache.hadoop.mapreduce.Job] - Running job: job_local1466554694_0001
 11 2017-03-15 22:16:28,473 INFO [org.apache.hadoop.mapred.LocalJobRunner] - OutputCommitter set in config null
 12 2017-03-15 22:16:28,479 INFO [org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter] - File Output Committer Algorithm version is 1
 13 2017-03-15 22:16:28,482 INFO [org.apache.hadoop.mapred.LocalJobRunner] - OutputCommitter is org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter
 14 2017-03-15 22:16:28,571 INFO [org.apache.hadoop.mapred.LocalJobRunner] - Waiting for map tasks
 15 2017-03-15 22:16:28,571 INFO [org.apache.hadoop.mapred.LocalJobRunner] - Starting task: attempt_local1466554694_0001_m_000000_0
 16 2017-03-15 22:16:28,609 INFO [org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter] - File Output Committer Algorithm version is 1
 17 2017-03-15 22:16:28,621 INFO [org.apache.hadoop.mapred.Task] -  Using ResourceCalculatorProcessTree : [ ]
 18 2017-03-15 22:16:28,624 INFO [org.apache.hadoop.mapred.MapTask] - Processing split: hdfs://localhost:9000/user/hadoop/input/file2.txt:0+32
 19 2017-03-15 22:16:28,679 INFO [org.apache.hadoop.mapred.MapTask] - (EQUATOR) 0 kvi 26214396(104857584)
 20 2017-03-15 22:16:28,679 INFO [org.apache.hadoop.mapred.MapTask] - mapreduce.task.io.sort.mb: 100
 21 2017-03-15 22:16:28,679 INFO [org.apache.hadoop.mapred.MapTask] - soft limit at 83886080
 22 2017-03-15 22:16:28,679 INFO [org.apache.hadoop.mapred.MapTask] - bufstart = 0; bufvoid = 104857600
 23 2017-03-15 22:16:28,679 INFO [org.apache.hadoop.mapred.MapTask] - kvstart = 26214396; length = 6553600
 24 2017-03-15 22:16:28,683 INFO [org.apache.hadoop.mapred.MapTask] - Map output collector class = org.apache.hadoop.mapred.MapTask$MapOutputBuffer
 25 2017-03-15 22:16:28,754 INFO [org.apache.hadoop.mapred.LocalJobRunner] - 
 26 2017-03-15 22:16:28,756 INFO [org.apache.hadoop.mapred.MapTask] - Starting flush of map output
 27 2017-03-15 22:16:28,757 INFO [org.apache.hadoop.mapred.MapTask] - Spilling map output
 28 2017-03-15 22:16:28,757 INFO [org.apache.hadoop.mapred.MapTask] - bufstart = 0; bufend = 92; bufvoid = 104857600
 29 2017-03-15 22:16:28,757 INFO [org.apache.hadoop.mapred.MapTask] - kvstart = 26214396(104857584); kvend = 26214380(104857520); length = 17/6553600
 30 2017-03-15 22:16:28,770 INFO [org.apache.hadoop.mapred.MapTask] - Finished spill 0
 31 2017-03-15 22:16:28,774 INFO [org.apache.hadoop.mapred.Task] - Task:attempt_local1466554694_0001_m_000000_0 is done. And is in the process of committing
 32 2017-03-15 22:16:28,785 INFO [org.apache.hadoop.mapred.LocalJobRunner] - map
 33 2017-03-15 22:16:28,785 INFO [org.apache.hadoop.mapred.Task] - Task 'attempt_local1466554694_0001_m_000000_0' done.
 34 2017-03-15 22:16:28,785 INFO [org.apache.hadoop.mapred.LocalJobRunner] - Finishing task: attempt_local1466554694_0001_m_000000_0
 35 2017-03-15 22:16:28,786 INFO [org.apache.hadoop.mapred.LocalJobRunner] - Starting task: attempt_local1466554694_0001_m_000001_0
 36 2017-03-15 22:16:28,791 INFO [org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter] - File Output Committer Algorithm version is 1
 37 2017-03-15 22:16:28,792 INFO [org.apache.hadoop.mapred.Task] -  Using ResourceCalculatorProcessTree : [ ]
 38 2017-03-15 22:16:28,793 INFO [org.apache.hadoop.mapred.MapTask] - Processing split: hdfs://localhost:9000/user/hadoop/input/file3.txt:0+30
 39 2017-03-15 22:16:28,823 INFO [org.apache.hadoop.mapred.MapTask] - (EQUATOR) 0 kvi 26214396(104857584)
 40 2017-03-15 22:16:28,823 INFO [org.apache.hadoop.mapred.MapTask] - mapreduce.task.io.sort.mb: 100
 41 2017-03-15 22:16:28,823 INFO [org.apache.hadoop.mapred.MapTask] - soft limit at 83886080
 42 2017-03-15 22:16:28,823 INFO [org.apache.hadoop.mapred.MapTask] - bufstart = 0; bufvoid = 104857600
 43 2017-03-15 22:16:28,823 INFO [org.apache.hadoop.mapred.MapTask] - kvstart = 26214396; length = 6553600
 44 2017-03-15 22:16:28,824 INFO [org.apache.hadoop.mapred.MapTask] - Map output collector class = org.apache.hadoop.mapred.MapTask$MapOutputBuffer
 45 2017-03-15 22:16:28,831 INFO [org.apache.hadoop.mapred.LocalJobRunner] - 
 46 2017-03-15 22:16:28,832 INFO [org.apache.hadoop.mapred.MapTask] - Starting flush of map output
 47 2017-03-15 22:16:28,832 INFO [org.apache.hadoop.mapred.MapTask] - Spilling map output
 48 2017-03-15 22:16:28,832 INFO [org.apache.hadoop.mapred.MapTask] - bufstart = 0; bufend = 78; bufvoid = 104857600
 49 2017-03-15 22:16:28,832 INFO [org.apache.hadoop.mapred.MapTask] - kvstart = 26214396(104857584); kvend = 26214384(104857536); length = 13/6553600
 50 2017-03-15 22:16:28,834 INFO [org.apache.hadoop.mapred.MapTask] - Finished spill 0
 51 2017-03-15 22:16:28,835 INFO [org.apache.hadoop.mapred.Task] - Task:attempt_local1466554694_0001_m_000001_0 is done. And is in the process of committing
 52 2017-03-15 22:16:28,839 INFO [org.apache.hadoop.mapred.LocalJobRunner] - map
 53 2017-03-15 22:16:28,839 INFO [org.apache.hadoop.mapred.Task] - Task 'attempt_local1466554694_0001_m_000001_0' done.
 54 2017-03-15 22:16:28,839 INFO [org.apache.hadoop.mapred.LocalJobRunner] - Finishing task: attempt_local1466554694_0001_m_000001_0
 55 2017-03-15 22:16:28,839 INFO [org.apache.hadoop.mapred.LocalJobRunner] - Starting task: attempt_local1466554694_0001_m_000002_0
 56 2017-03-15 22:16:28,842 INFO [org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter] - File Output Committer Algorithm version is 1
 57 2017-03-15 22:16:28,843 INFO [org.apache.hadoop.mapred.Task] -  Using ResourceCalculatorProcessTree : [ ]
 58 2017-03-15 22:16:28,844 INFO [org.apache.hadoop.mapred.MapTask] - Processing split: hdfs://localhost:9000/user/hadoop/input/file1.txt:0+20
 59 2017-03-15 22:16:28,888 INFO [org.apache.hadoop.mapred.MapTask] - (EQUATOR) 0 kvi 26214396(104857584)
 60 2017-03-15 22:16:28,888 INFO [org.apache.hadoop.mapred.MapTask] - mapreduce.task.io.sort.mb: 100
 61 2017-03-15 22:16:28,888 INFO [org.apache.hadoop.mapred.MapTask] - soft limit at 83886080
 62 2017-03-15 22:16:28,888 INFO [org.apache.hadoop.mapred.MapTask] - bufstart = 0; bufvoid = 104857600
 63 2017-03-15 22:16:28,888 INFO [org.apache.hadoop.mapred.MapTask] - kvstart = 26214396; length = 6553600
 64 2017-03-15 22:16:28,889 INFO [org.apache.hadoop.mapred.MapTask] - Map output collector class = org.apache.hadoop.mapred.MapTask$MapOutputBuffer
 65 2017-03-15 22:16:28,893 INFO [org.apache.hadoop.mapred.LocalJobRunner] - 
 66 2017-03-15 22:16:28,894 INFO [org.apache.hadoop.mapred.MapTask] - Starting flush of map output
 67 2017-03-15 22:16:28,894 INFO [org.apache.hadoop.mapred.MapTask] - Spilling map output
 68 2017-03-15 22:16:28,894 INFO [org.apache.hadoop.mapred.MapTask] - bufstart = 0; bufend = 56; bufvoid = 104857600
 69 2017-03-15 22:16:28,894 INFO [org.apache.hadoop.mapred.MapTask] - kvstart = 26214396(104857584); kvend = 26214388(104857552); length = 9/6553600
 70 2017-03-15 22:16:28,895 INFO [org.apache.hadoop.mapred.MapTask] - Finished spill 0
 71 2017-03-15 22:16:28,896 INFO [org.apache.hadoop.mapred.Task] - Task:attempt_local1466554694_0001_m_000002_0 is done. And is in the process of committing
 72 2017-03-15 22:16:28,899 INFO [org.apache.hadoop.mapred.LocalJobRunner] - map
 73 2017-03-15 22:16:28,899 INFO [org.apache.hadoop.mapred.Task] - Task 'attempt_local1466554694_0001_m_000002_0' done.
 74 2017-03-15 22:16:28,899 INFO [org.apache.hadoop.mapred.LocalJobRunner] - Finishing task: attempt_local1466554694_0001_m_000002_0
 75 2017-03-15 22:16:28,899 INFO [org.apache.hadoop.mapred.LocalJobRunner] - map task executor complete.
 76 2017-03-15 22:16:28,901 INFO [org.apache.hadoop.mapred.LocalJobRunner] - Waiting for reduce tasks
 77 2017-03-15 22:16:28,902 INFO [org.apache.hadoop.mapred.LocalJobRunner] - Starting task: attempt_local1466554694_0001_r_000000_0
 78 2017-03-15 22:16:28,914 INFO [org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter] - File Output Committer Algorithm version is 1
 79 2017-03-15 22:16:28,915 INFO [org.apache.hadoop.mapred.Task] -  Using ResourceCalculatorProcessTree : [ ]
 80 2017-03-15 22:16:28,919 INFO [org.apache.hadoop.mapred.ReduceTask] - Using ShuffleConsumerPlugin: org.apache.hadoop.mapreduce.task.reduce.Shuffle@4fb755c9
 81 2017-03-15 22:16:28,932 INFO [org.apache.hadoop.mapreduce.task.reduce.MergeManagerImpl] - MergerManager: memoryLimit=1945842432, maxSingleShuffleLimit=486460608, mergeThreshold=1284256000, ioSortFactor=10, memToMemMergeOutputsThreshold=10
 82 2017-03-15 22:16:28,934 INFO [org.apache.hadoop.mapreduce.task.reduce.EventFetcher] - attempt_local1466554694_0001_r_000000_0 Thread started: EventFetcher for fetching Map Completion Events
 83 2017-03-15 22:16:28,980 INFO [org.apache.hadoop.mapreduce.task.reduce.LocalFetcher] - localfetcher#1 about to shuffle output of map attempt_local1466554694_0001_m_000002_0 decomp: 64 len: 68 to MEMORY
 84 2017-03-15 22:16:28,984 INFO [org.apache.hadoop.mapreduce.task.reduce.InMemoryMapOutput] - Read 64 bytes from map-output for attempt_local1466554694_0001_m_000002_0
 85 2017-03-15 22:16:28,986 INFO [org.apache.hadoop.mapreduce.task.reduce.MergeManagerImpl] - closeInMemoryFile -> map-output of size: 64, inMemoryMapOutputs.size() -> 1, commitMemory -> 0, usedMemory ->64
 86 2017-03-15 22:16:28,991 INFO [org.apache.hadoop.mapreduce.task.reduce.LocalFetcher] - localfetcher#1 about to shuffle output of map attempt_local1466554694_0001_m_000001_0 decomp: 64 len: 68 to MEMORY
 87 2017-03-15 22:16:28,992 INFO [org.apache.hadoop.mapreduce.task.reduce.InMemoryMapOutput] - Read 64 bytes from map-output for attempt_local1466554694_0001_m_000001_0
 88 2017-03-15 22:16:28,992 INFO [org.apache.hadoop.mapreduce.task.reduce.MergeManagerImpl] - closeInMemoryFile -> map-output of size: 64, inMemoryMapOutputs.size() -> 2, commitMemory -> 64, usedMemory ->128
 89 2017-03-15 22:16:28,993 INFO [org.apache.hadoop.mapreduce.task.reduce.LocalFetcher] - localfetcher#1 about to shuffle output of map attempt_local1466554694_0001_m_000000_0 decomp: 87 len: 91 to MEMORY
 90 2017-03-15 22:16:28,994 INFO [org.apache.hadoop.mapreduce.task.reduce.InMemoryMapOutput] - Read 87 bytes from map-output for attempt_local1466554694_0001_m_000000_0
 91 2017-03-15 22:16:28,994 INFO [org.apache.hadoop.mapreduce.task.reduce.MergeManagerImpl] - closeInMemoryFile -> map-output of size: 87, inMemoryMapOutputs.size() -> 3, commitMemory -> 128, usedMemory ->215
 92 2017-03-15 22:16:28,994 INFO [org.apache.hadoop.mapreduce.task.reduce.EventFetcher] - EventFetcher is interrupted.. Returning
 93 2017-03-15 22:16:28,995 INFO [org.apache.hadoop.mapred.LocalJobRunner] - 3 / 3 copied.
 94 2017-03-15 22:16:28,995 INFO [org.apache.hadoop.mapreduce.task.reduce.MergeManagerImpl] - finalMerge called with 3 in-memory map-outputs and 0 on-disk map-outputs
 95 2017-03-15 22:16:29,004 INFO [org.apache.hadoop.mapred.Merger] - Merging 3 sorted segments
 96 2017-03-15 22:16:29,005 INFO [org.apache.hadoop.mapred.Merger] - Down to the last merge-pass, with 3 segments left of total size: 183 bytes
 97 2017-03-15 22:16:29,006 INFO [org.apache.hadoop.mapreduce.task.reduce.MergeManagerImpl] - Merged 3 segments, 215 bytes to disk to satisfy reduce memory limit
 98 2017-03-15 22:16:29,006 INFO [org.apache.hadoop.mapreduce.task.reduce.MergeManagerImpl] - Merging 1 files, 215 bytes from disk
 99 2017-03-15 22:16:29,007 INFO [org.apache.hadoop.mapreduce.task.reduce.MergeManagerImpl] - Merging 0 segments, 0 bytes from memory into reduce
100 2017-03-15 22:16:29,007 INFO [org.apache.hadoop.mapred.Merger] - Merging 1 sorted segments
101 2017-03-15 22:16:29,008 INFO [org.apache.hadoop.mapred.Merger] - Down to the last merge-pass, with 1 segments left of total size: 203 bytes
102 2017-03-15 22:16:29,008 INFO [org.apache.hadoop.mapred.LocalJobRunner] - 3 / 3 copied.
103 2017-03-15 22:16:29,049 INFO [org.apache.hadoop.conf.Configuration.deprecation] - mapred.skip.on is deprecated. Instead, use mapreduce.job.skiprecords
104 2017-03-15 22:16:29,186 INFO [org.apache.hadoop.mapred.Task] - Task:attempt_local1466554694_0001_r_000000_0 is done. And is in the process of committing
105 2017-03-15 22:16:29,190 INFO [org.apache.hadoop.mapred.LocalJobRunner] - 3 / 3 copied.
106 2017-03-15 22:16:29,190 INFO [org.apache.hadoop.mapred.Task] - Task attempt_local1466554694_0001_r_000000_0 is allowed to commit now
107 2017-03-15 22:16:29,209 INFO [org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter] - Saved output of task 'attempt_local1466554694_0001_r_000000_0' to hdfs://localhost:9000/user/hadoop/output/_temporary/0/task_local1466554694_0001_r_000000
108 2017-03-15 22:16:29,210 INFO [org.apache.hadoop.mapred.LocalJobRunner] - reduce > reduce
109 2017-03-15 22:16:29,210 INFO [org.apache.hadoop.mapred.Task] - Task 'attempt_local1466554694_0001_r_000000_0' done.
110 2017-03-15 22:16:29,210 INFO [org.apache.hadoop.mapred.LocalJobRunner] - Finishing task: attempt_local1466554694_0001_r_000000_0
111 2017-03-15 22:16:29,210 INFO [org.apache.hadoop.mapred.LocalJobRunner] - reduce task executor complete.
112 2017-03-15 22:16:29,473 INFO [org.apache.hadoop.mapreduce.Job] - Job job_local1466554694_0001 running in uber mode : false
113 2017-03-15 22:16:29,474 INFO [org.apache.hadoop.mapreduce.Job] -  map 100% reduce 100%
114 2017-03-15 22:16:29,475 INFO [org.apache.hadoop.mapreduce.Job] - Job job_local1466554694_0001 completed successfully
115 2017-03-15 22:16:29,487 INFO [org.apache.hadoop.mapreduce.Job] - Counters: 35
116     File System Counters
117         FILE: Number of bytes read=4131
118         FILE: Number of bytes written=1128147
119         FILE: Number of read operations=0
120         FILE: Number of large read operations=0
121         FILE: Number of write operations=0
122         HDFS: Number of bytes read=258
123         HDFS: Number of bytes written=165
124         HDFS: Number of read operations=33
125         HDFS: Number of large read operations=0
126         HDFS: Number of write operations=6
127     Map-Reduce Framework
128         Map input records=3
129         Map output records=12
130         Map output bytes=226
131         Map output materialized bytes=227
132         Input split bytes=342
133         Combine input records=12
134         Combine output records=10
135         Reduce input groups=6
136         Reduce shuffle bytes=227
137         Reduce input records=10
138         Reduce output records=6
139         Spilled Records=20
140         Shuffled Maps =3
141         Failed Shuffles=0
142         Merged Map outputs=3
143         GC time elapsed (ms)=0
144         Total committed heap usage (bytes)=1592262656
145     Shuffle Errors
146         BAD_ID=0
147         CONNECTION=0
148         IO_ERROR=0
149         WRONG_LENGTH=0
150         WRONG_MAP=0
151         WRONG_REDUCE=0
152     File Input Format Counters 
153         Bytes Read=82
154     File Output Format Counters 
155         Bytes Written=165

View Code

结果：

1 Hello    file3.txt:1;
2 MapReduce    file3.txt:2;file1.txt:1;file2.txt:1;
3 bye    file3.txt:1;
4 is    file1.txt:1;file2.txt:2;
5 powerful    file2.txt:1;
6 simple    file2.txt:1;file1.txt:1;

posted on 2017-03-15 22:30 Honey_Badger 阅读(545) 评论(0) 编辑收藏举报

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