UNIX for Beginners Questions & Answers

1|A,B,C,A
2|A,D,D
3|A,B,B

A   3
B   2
C   1
D   1

gawk '
BEGIN{FS="|";OFS="\t"}
{
   a=split($2,b,",")
   for(i=1;i<=a;i++){
      if(count[b[i]]++==0){
         total[b[i]]++
      }
   }
}
END{
   for(k in total){
      print k "\t" total[k]
   }
}

A   1
B   1
C   1
D   1

awk -F"|" -vOFS="\t" '

        {a = split ($2, b, ",")
         for (i=1; i<=a; i++)   if (!count[b[i]]++)     total[b[i]]++
         delete count
        }

END     {for (k in total)       print k "\t" total[k]
        }
' file
A    3
B    2
C    1
D    1

awk '
{for (i=2; i<=NF; i++) if (! line_fields[$i, NR]++) field_count[$i]++ }
END { for (i in field_count) print i "\t" field_count[i] }
' FS="[|,]" input