Код:
var a,b:string;
    x,y,z:array [1..1001] of integer;
    i,f,nx,ny,nz:longint;
 
 begin

    readln(a);
    readln(b);

    nx:=length(a);
    ny:=length(b);

    for i:=1 to nx do
      val(a[i],x[nx-i+1],f);
  
    for i:=1 to ny do
      val(b[i],y[ny-i+1],f);

    if nx>ny then nz:=nx
             else nz:=ny;

    for i:=1 to nz do
     begin
      z[i]:=z[i]+y[i]+x[i];
      if z[i]>9 then begin z[i]:=z[i] mod 10;z[i+1]:=1;end;
     end;

    if z[nz+1]<>0 then nz:=nz+1;

    for i:=nz downto 1 do
     write(z[i]);

 end.