BEGIN{P["0_0"]=1; Hx=Hy=Tx=Ty=0}
function abs(x) { return x>0?x:-x}
{
  print "==", Hx","Hy, ";", Tx","Ty, "==", $1, $2
  for(i=1;i<=$2;i++){
    if($1=="R") {Hx++}
    if($1=="L") {Hx--}
    if($1=="U") {Hy++}
    if($1=="D") {Hy--}
    dh = abs(Hx-Tx)  # tension horizontale
    dv = abs(Hy-Ty)  # tension vertivale
    if(dh>1 && $1=="R") {Tx++; if (dv>0) {Ty=Hy}}
    if(dh>1 && $1=="L") {Tx--; if (dv>0) {Ty=Hy}}
    if(dv>1 && $1=="U") {Ty++; if (dh>0) {Tx=Hx}}
    if(dv>1 && $1=="D") {Ty--; if (dh>0) {Tx=Hx}}
    P[Ty "_" Tx]=1
    print Hx, Hy, ";", "dh:"dh, "dv:"dv, "=>", Tx, Ty
  }
}
END{print length(P)}