RosettaCodeData/Task/Balanced-brackets/AWK/balanced-brackets.awk

#!/usr/bin/awk -f
BEGIN {
   print isbb("[]")
   print isbb("][")
   print isbb("][][")
   print isbb("[][]")
   print isbb("[][][]")
   print isbb("[]][[]")
}

function isbb(x) {
   s = 0
   for (k=1; k<=length(x); k++) {
    c = substr(x,k,1)
    if (c=="[") {s++}
    else { if (c=="]") s--  }

        if (s<0) {return 0}
   }
   return (s==0)
}