Shell Programming and Scripting

nr=3                                 # nr of output files
CHARS=$(<infile)                     # read characters
for (( n=0; n<${#CHARS}; n++ )) do   # for each character
  to=$(( RANDOM%nr+1 ))              # determine to which file
  for (( i=1; i<=nr; i++ )); do      # for each outfile
    if (( to == i )); then           # if the char goes here
      printf ${CHARS:n:1}            # write the character
    else                             #
      printf " "                     # write a space if no char
    fi >> outfile$i                  # append character to file
  done                               #
done                                 #
echo | tee -a outfile? >/dev/null    # write \n to every outfile