fcn validateIBAN(iban){
   iban=iban-" \t";
   alphaNums.matches(iban) and (ibans.find(iban[0,2])==iban.len()) and
   ( (iban[4,*]+iban[0,4]).apply("toInt",36) : mod97(_) == 1 )
}
fcn mod97(str){
   n:=0; m:=9; M:=0; while(N:=str[n,m]){
      M=((M.toString()+N).toInt()) % 97;
      n+=m; m=7;
   }
   M
}