program kkxx;
  var
    a,time,name1,name2:array[1..10000] of longint;
    f:array[1..100000] of boolean;
    i,j,n,p,r,t,max,min,t1,c:longint;
    procedure sort(l,r:longint);
      var
         i,j,x,y: longint;
      begin
         i:=l;
         j:=r;
         x:=time[(l+r) div 2];
         repeat
           while time[i]<x do
            inc(i);
           while x<time[j] do
            dec(j);
           if not(i>j) then
             begin
                y:=time[i];
                time[i]:=time[j];
                time[j]:=y;
                y:=a[i];
                a[i]:=a[j];
                a[j]:=y;
                inc(i);
                j:=j-1;
             end;
         until i>j;
         if l<j then
           sort(l,j);
         if i<r then
           sort(i,r);
      end;
  begin
    assign(input,'salenet.in');reset(input);
    assign(output,'salenet.out');rewrite(output);
    readln(n,p);
    for i:=1 to p do
      readln(a[i],time[i]);
    fillchar(f,sizeof(f),false);
    readln(r);
    for i:=1 to r do
      readln(name1[i],name2[i]);
 
    sort(1,p);
    t:=0;
    while t<p do
      begin
        inc(t);
        if not f[a[t]] then begin f[a[t]]:=true; max:=max+time[t]; end;
        for i:=1 to r do
          if name1[i]=a[t] then f[name2[i]]:=true;
      end;
    for i:=1 to n do
      if f[i] then inc(min)
              else begin inc(t1); c:=i; break; end;
    if t1=0 then begin writeln('YES'); writeln(max); end
            else begin writeln('NO'); writeln(c); end;
    if min=n then
             else
 
 
    close(input);close(output);
  end.