[leetcode]Word Frequency

awk '{for(i=1;i<=NF;i++){a[$i]++;count++}} END{for(j in a){print j,a[j]}}' words.txt | sort -k 2 -nr

or

cat words.txt|tr -s '\t| ' '\n'|sort|uniq -c|sort -nk1 -r|awk '{print $2" "$1}'