shell求简单分列合并解法，高手给看看！多谢！

Question

求简单shell分列合并解法，多谢！
数据：
stra b
stra c
stra d
strb 1
strb 2
strb 3

希望结果：
stra
b
c
d
strb
1
2
3

Answer 1

awk '{print a[$1]?$2:a[$1]=$1RS$2}' file

Answer 2

回复 1# spouter

1. echo "stra b
2. stra c
3. stra d
4. strb 1
5. strb 2
6. strb 3" |awk '{print $1==v?$2:$1"\n"$2;v=$1}'
7. stra
8. b
9. c
10. d
11. strb
12. 1
13. 2
14. 3

复制代码

Answer 3

1. cat urfile1 | tr ' ' '\n'
2. stra
3. b
4. stra
5. c
6. stra
7. d
8. strb
9. 1
10. strb
11. 2
12. strb
13. 3

复制代码

Answer 4

1. echo "stra b
2. stra c
3. stra d
4. strb 1
5. strb 2
6. strb 3" |
7. sed -n -r '
8. 1h
9. {
10.      1!H
11.      x
12.      s/([^ ]*)(.*)([^\n]*)\n\1 (.*)/\1\2 \3 \4/
13.      h
14. }
16. ${
17. s/ +/\n/g
18. p
19. }'
21. stra
22. b
23. c
24. d
25. strb
26. 1
27. 2
28. 3

复制代码

Answer 5

2. # 前几天看到bash去重复的方法，用在这里似乎也可以
4. #!/bin/bash
6. $ s="\n"
7. while read line1 line2
8. do
9.      if [ "$s" == "${s/ $line1}" ]; then
10.      echo -e $line1"\n"$line2 && s="$s $line1"
11.      else
12.      echo $line2
13.      fi
14. done <file

复制代码stra
b
c
d
strb
1
2
3

Answer 6

回复 1# spouter

awk -f str.awk filename

str.awk:

BEGIN { FS = " " }
{ if ( NR ==1 || NR == 4)
print $1,"\n",$2
else
  print "",$2
}

filename＝要处理的内容。