fett

Program NoName; 

Var 
  b,x,z,c,v,q,w,e:integer; 
   n:array [ 1..3 ] of integer; 
   s:array [ 1..6 ] of integer; 
   a:array [ 1..7 ] of boolean; 

Begin 
  b:=1; a[7]:=false;
  for x:=1 to 6 do 
    Begin 
      ReadLn( s[x]);
      a[x]:=false; 
    end; 
  for z:=1 to 4 do
    for x:=z+1 to 5 do
      for c:=x+1 to 6 do 
        Begin 
          a[z]:=true; 
          a[x]:=true; 
          a[c]:=true; 
          for v:=1 to 6 do 

              if a[v]=false then 
                Begin 

                  n[b]:=v;
                  b:=b+1; 
                end; 

          q:=n[1]; 
          w:=n[2]; 
          e:=n[3]; 
          b:=1; 
          for v:=1 to 3 do 
            n[v]:=0; 
              if s[z]+s[x]+s[c]=s[q]+s[w]+s[e] then
              a[7]:= true;
          for v:=1 to 6 do 
            a[v]:=false;
        end; 
        If a[7]=false then 
        WriteLn( 'NO' )
        else
        WriteLn( 'YES' );
end.