a awk script to print the field number with empty line

emptyfield.awk

#!/bin/awk -f
#will fail with several case, still investigating 
BEGIN{
        print "begin";
}
{
        count=0;
        for(f=1;f<=NF;f++){
                if($f==""){
                        if(count==0){
                                arr[count]=f;
                        }
                        else{
                                exist=0;
                                for(i=0;i<=count;i++){
                                        if(arr[i]==f){
                                                exist=1;
                                        }
                                }
                                if(exist==0){
                                        arr[count]=f;
                                }
                        }
                        count++;
                }
        }
}
END{
        for(j=0;j<=count;j++){
                print "empty field: " arr[j];
        }
        print "completed";
}