I try to learn a new skill for shell script. So now I receive a lesson from my teacher about move file to new directory.

Question

There is a file pattern

A_20180423_0015 B_20180501_0045 C_20180426_0045 

and want to moving files to those directories like /new/destpath/A/20180423/0015,0030,0045 each directory have a 3 files

in my script i write

 #! /bin/bash
cd /app/Moving/DEST_PATH
mkdir A B C D
cd /app/Moving/DEST_PATH/A
MakesubA=$(for itype in A;do for ((i=1;i<=10;i++));do for ((itime=15;itime<=45;itime=itime+15));do mkdir $itype_$(date --date "$i day ago" +"%Y%m%d")_00$itime ;done;done;done)
cd ..
cd /app/Moving/DEST_PATH/B
MakesubB=$(for itype in B;do for ((i=1;i<=10;i++));do for ((itime=15;itime<=45;itime=itime+15));do mkdir $itype_$(date --date "$i day ago" +"%Y%m%d")_00$itime ;done;done;done)
cd ..
cd /app/Moving/DEST_PATH/C
MakesubC=$(for itype in C;do for ((i=1;i<=10;i++));do for ((itime=15;itime<=45;itime=itime+15));do mkdir $itype_$(date --date "$i day ago" +"%Y%m%d")_00$itime ;done;done;done)
cd ..
cd /app/Moving/DEST_PATH/D
MakesubD=$(for itype in D;do for ((i=1;i<=10;i++));do for ((itime=15;itime<=45;itime=itime+15));do mkdir $itype_$(date --date "$i day ago" +"%Y%m%d")_00$itime ;done;done;done)
cd ..

and i try to figure it out to use loop or it else but i don't know which use to select each file to each directory.

You have files that basically have a destination path encoded in their filenames.

The file called A_20180423_0015 should be moved to A/20180423/0015 (I'm assuming 0015 is the new name of the file in the directory A/20180423), which is a pathname that is the same as the original filename but with the underscores replaced by slashes.

This means that this exercise is about replacing characters in strings.

There is no need to go through and create destination directories for every single possible date because the destination is already encoded in the filename of the files.

I'm not entirely sure where the original files are located, or whether you can just use [A-Z]_*_* as a pattern to match them in the current directory (I'm going to assume you can).

for source_filename in [A-Z]_*_*; do
 target_pathname=$source_filename//_//
 mkdir -p "$target_pathname%/*"
 mv "$source_filename" "$target_pathname"
done

If we start out with

.
|-- A_20180423_0015
|-- B_20180501_0045
`-- C_20180426_0045

0 directory, 3 files

... and run the above code, then we'll end up with

.
|-- A/
| `-- 20180423/
| `-- 0015
|-- B/
| `-- 20180501/
| `-- 0045
`-- C/
 `-- 20180426/
 `-- 0045

6 directories, 3 files

Annotated code:

# Loop over all names in the current directory that matches the given pattern.
for source_filename in [A-Z]_*_*; do
 # Replace all underscores in the found name with slashes.
 # We use bash's $parameter//pattern/replacement pattern substitution
 # to do this.
 # If you need to append a path to this, just do so with
 # target_pathname="/some/path/$source_filename//_//"
 target_pathname=$source_filename//_//

 # Make sure that the target directory exists.
 # With $target_pathname%/* we remove the filename component of
 # the target pathname to get the directory of the destination file.
 # You may change this to the following if you wish:
 # mkdir -p "$( dirname "$target_pathname" )"
 mkdir -p "$target_pathname%/*"

 # Move the file into place.
 mv "$source_filename" "$target_pathname"
done

If I have misunderstood the question and the files should retain their original filenames, but be moved into directories corresponding to the filename, i.e. A_20180423_0015 should be moved to A/20180423/0015/A_20180423_0015, then we only have to change a few characters in the code above:

mkdir -p "$target_pathname%/*"

changes to

mkdir -p "$target_pathname"

This change would give us

.
|-- A/
| `-- 20180423/
| `-- 0015/
| `-- A_20180423_0015
|-- B/
| `-- 20180501/
| `-- 0045/
| `-- B_20180501_0045
`-- C/
 `-- 20180426/
 `-- 0045/
 `-- C_20180426_0045

9 directories, 3 files

For the case when the source files are located in another directory than the current one:

for source_pathname in /some/source/path/[A-Z]_*_*; do
 source_filename=$source_pathname##*/
 target_pathname="some/target/path/$source_filename//_//"
 mkdir -p "$target_pathname"
 mv "$source_pathname" "$target_pathname"
done