Shell Programming and Scripting

awk '
{
   if ( arr[$1] == "" )
        arr[$1]=$1 " " $2
   else
        arr[$1]=arr[$1] " " $2
}
END{
   for( key in arr)
        print arr[key]
}
' file

function isort(A,n,     i,j,t) {
    for (i = 2; i <= n; i++)
        for (j = i; j > 1 && A[j-1] > A[j]; j--) {
              # swap A[j-1] and A[j]
              t = A[j-1]; A[j-1] = A[j]; A[j] = t
        }
}

{
  arr[$1] = ($1 in arr) ? arr[$1] OFS $2 : $2
}

END {
  for ( i in arr ) {
    n=split(arr[i], tmpA, OFS)
    isort(tmpA, n)
    printf("%s%s", i, OFS )
    for(j=1; j <= n; j++)
       printf("%s%s", tmpA[j], (j==n) ? "\n" : OFS)
  }
}

$ sort -n -k 1,1 -k 2,2 steve.txt | nawk -f steve1.awk 
2 3 4
3 0 7 9
1 5 6 7