给出一个单词W,我想从/usr/dict / words找到包含W中所有字母的所有单词.
例如,“bat”应该返回“bat”和“tab”(而不是“table”).
例如,“bat”应该返回“bat”和“tab”(而不是“table”).
word=$1
sortedWord=`echo $word | grep -o . | sort | tr -d '\n'`
while read line
do
sortedLine=`echo $line | grep -o . | sort | tr -d '\n'`
if [ "$sortedWord" == "$sortedLine" ]
then
echo $line
fi
done < /usr/dict/words
有没有更好的办法？我更喜欢使用基本命令(而不是perl / awk等),但所有的解决方案都是欢迎的！
这是一个awk实现.它在“W”中找到这些字母的单词.
dict="/usr/share/dict/words"
word=$1
awk -vw="$word" 'BEGIN{
m=split(w,c,"")
for(p=1;p<=m;p++){ chars[c[p]]++ }
}
length($0)==length(w){
f=0;g=0
n=split($0,t,"")
for(o=1;o<=n;o++){
if (!( t[o] in chars) ){
f=1; break
}else{ st[t[o]]++ }
}
if (!f || $0==w){
for(z in st){
if ( st[z] != chars[z] ) { g=1 ;break}
}
if(!g){ print "found: "$0 }
}
delete st
}' $dict
产量
$wc -l < /usr/share/dict/words 479829 $time ./shell.sh look found: kolo found: look real 0m1.361s user 0m1.074s sys 0m0.015s
更新：更改算法,使用排序
dict="/usr/share/dict/words"
awk 'BEGIN{
w="table"
m=split(w,"")
b=asort(c,chars)
}
length($0)==length(w){
f=0
n=split($0,"")
e=asort(t,d)
for(i=1;i<=e;i++) {
if(d[i]!=chars[i]){
f=1;break
}
}
if(!f) print $0
}' $dict
产量
$time ./shell.sh #looking for table ablet batel belat blate bleat tabel table real 0m1.416s user 0m1.343s sys 0m0.014s $time ./shell.sh #looking for chairs chairs ischar rachis real 0m1.697s user 0m1.660s sys 0m0.014s $time perl perl.pl #using beamrider's Perl script table tabel ablet batel blate bleat belat real 0m2.680s user 0m1.633s sys 0m0.881s $time perl perl.pl # looking for chairs chairs ischar rachis real 0m14.044s user 0m8.328s sys 0m5.236s
