$1=K*K        # $1 := K**2+1;
$1=$1+1
$0=K          # $0 := K;
$2=1          # $2 := 1;
$3=N/K        # $3 := N/K;
while$0<=$3   # if $0<=(N/K):
  $2=$0       #   $1,$0,$2 := ($1*K+$0),($1),($0);
  $0=$1
  $1=$0*K
  $1=$1+$2
end           # end
if$0<=N       # if $0<=N:
  $3=N/$0     #   $3 := N/$0+1;
  $3=$3+1
  $1=$1*$3    #   $1 := $1*$3+$0;
  $1=$1+$0
  $0=$0*$3    #   $0 := $0*$3+$2;
  $0=$0+$2
end           # end
$2=$0*N       # $2 := $0*N;
$3=$1-$0
ifM==0        # if M==0:
  $3=$3+K     #   $2 := $2-($1-$0+K-1)/K;
  $3=$3-1
  $3=$3/K
  $2=$2-$3
end           # end
ifM>0         # if M>0:
  $4=M-1      #   $4 := M-1;
  $5=$3/K     #   $2 := $2+(($1-$0)/K)*(M-1);
  $5=$5*$4
  $2=$2+$5
  $3=$3%K     #   $2 := $2+(($1-$0)%K)*(M-1)/K;
  $3=$3*$4
  $3=$3/K
  $2=$2+$3
end           # end
$0=$2/$1      # $0 := $2/$1+N;
$0=$0+N
return$0      # return $0;