> pascal的
> 
> 
> program xxxxxx;
> var
>   n,w,m:longint;
>   d:array[1..1000,1..1000]of longint;
>   f:array[1..1000]of longint;
>   i,j,k,a,b,t,bj,ff:longint;
>   bb:boolean;
> begin
>   readln(ff);
>   for k:=1 to ff do
>   begin
>     bb:=false;
>     readln(n,m,w);
>     for i:=1 to m do
>     begin
>       read(a,b,t);
>       d[a,b]:=t;
>       d[b,a]:=t;
>     end;
>     for i:=1 to w do
>     begin
>       read(a,b,t);
>       d[a,b]:=-t;
>     end;
>     for i:=2 to n do f[i]:=d[1,i];
>     for t:=1 to n-1 do
>     begin
>       bj:=0;
>       for i:=1 to n do
>       for j:=1 to n do
>       if (i<>j)and(d[i,j]<>0)and(f[i]<>0) then
>       if (d[i,j]+f[i]<f[j])or(f[j]=0) then
>       begin
>         bj:=1;
>         f[j]:=f[i]+d[i,j];
>       end;
>       if bj=0 then break;
>     end;
>     for i:=1 to n do
>     for j:=1 to n do
>     if f[i]+d[i,j]<f[j] then bb:=true;
>     if bb then writeln('YES') else writeln('NO');
>   end;
> end.