在Linux中生成字符串的文本文件

Question

I need to generate text files of strings of 3 characters, with duplicate strings allowed. I've searched for a method to do this, but I can only find methods to generate completely random text. Since I'm still a newbie, I have no idea of how to proceed. Any assistance will be greatly appreciated.

Answer 1

Using bash to get combinations inefficiently:

a[0]=a; a[1]=b; a[2]=c;
for i in $(seq 0 26); do
  r1=$(expr $i % 3)
  r2=$(expr $i / 3 % 3)
  r3=$(expr $i / 9 % 3)
  echo ${a[$r1]}${a[$r2]}${a[$r3]}
done

A faster way:

a[0]=a; a[1]=b; a[2]=c;

for r1 in $(seq 0 2); do
  for r2 in $(seq 0 2); do
    for r3 in $(seq 0 2); do
      echo ${a[$r1]}${a[$r2]}${a[$r3]}
    done
  done
done