Shell Programming and Scripting

HI all

I'm trying to write an awk script to print the min and max value in a range(s) contained in another file - the range values are in $2
EG
114,7964,1,y,y,n
114,7965,1,y,y,n
114,7966,1,y,y,n
114,7967,1,y,y,n
114,7969,1,y,y,n
114,7970,1,y,y,n
114,7971,1,y,y,n
114,7972,1,y,y,n
114,7973,1,y,y,n
114,7974,1,y,y,n
114,7977,1,y,y,n
114,7980,1,y,y,n
114,7981,1,y,y,n
114,7983,1,y,y,n

The output should produce
7964
7967
7969
7974
7977
7977
7980
7983

Or ideally
7964 - 7967
7969 - 7974
7977
7980 - 7983

SO far I have this awk script
BEGIN{
FS=OFS=","
nxt=0
}
$2!=nxt {print $2;tmp=$2;nxt=int($2+1)}
Which produces the wrong max figure
i.e.
7964
7966
7969
7971
7973
etc .....

Note the extra 7971 ??

Any advice ??

thanks

I'm not sure if your posted 'desired' output is what you actually want based on on explanation:

Code:

7964 - 7967
7969 - 7974
7977
7980 - 7983

The '7980 - 7983' has a 'hole' in the range - 1982.
Here's something to try:

nawk -f mud.awk myFile

mud.awk:

Code:

BEGIN {
  FS=OFS=","
}
!beg { beg=prev=int($2);next}
$2 != prev+1 { printf("%d - %d\n", beg, prev); beg=prev=last=$2;next}
{prev=last=$2}

END {
  printf("%d - %d\n", beg, last)
}

Sorry - typo.
I've tried a different approach since I posted --

BEGIN{
FS=OFS=","
nxt=0
}
{
if (( $2 != nxt ))
{print tmp;print $2 "-";tmp=$2;nxt=int($2+1)}
else
{tmp=$2;nxt=int($2+1)}
}
END{
print tmp
}

Which basically works
Thanks again vgersh

Your solution is much better

Thanks Again for your help