factr.sh

来自「Shall高级编程」· Shell 代码 · 共 30 行

#!/bin/bash
# factr.sh: Factor a number

MIN=2       # Will not work for number smaller than this.
E_NOARGS=65
E_TOOSMALL=66

if [ -z $1 ]
then
  echo "Usage: $0 number"
  exit $E_NOARGS
fi

if [ "$1" -lt "$MIN" ]
then
  echo "Number to factor must be $MIN or greater."
  exit $E_TOOSMALL
fi  

# Exercise: Add type checking (to reject non-integer arg).

echo "Factors of $1:"
# -------------------------------------------------------------------------------
echo "$1[p]s2[lip/dli%0=1dvsr]s12sid2%0=13sidvsr[dli%0=1lrli2+dsi!>.]ds.xd1<2"|dc
# -------------------------------------------------------------------------------
# Above line of code written by Michel Charpentier &lt;[e-mail]&gt;.
# Used in ABS Guide with permission (thanks!).

 exit 0