program plee;
var t,a:integer;
n:integer;
ple:array[1..1000,1..3]of integer;
pi,po:text;
x1,x2:integer;
js1,js2:longint;
zl:longint;
zx:longint;
procedure go(aa:integer);
var x:integer;
begin
for x:=aa to n do
begin
if (((js1+ple[x,1]<t) or (js2+ple[x,2]<a)) and (zl+ple[x,3]<zx)) then
begin
js1:=js1+ple[x,1];
js2:=js2+ple[x,2];
zl:=zl+ple[x,3];
go(x+1);
js1:=js1-ple[x,1];
js2:=js2-ple[x,2];
zl:=zl-ple[x,3];
end;
if (((js1+ple[x1,1]>=t) and (js2+ple[x,2]>=a)) and (zl+ple[x,3]<zx)) then
zx:=zl+ple[x,3];
end;
end;
begin
assign(pi,'ple.in');
reset(pi);
readln(pi,t,a);
readln(pi,n);
for x1:=1 to n do readln(pi,ple[x1,1],ple[x1,2],ple[x1,3]);
close(pi);
js1:=0;
js2:=0;
zx:=maxint;
go(1);
assign(po,'ple.out');
rewrite(po);
writeln(po,zx);
close(po);
end.