var f1,f2:text;
    i,n,m,k:longint;
    v1,v2:array[0..100010] of longint;
begin
        assign(f1,'stergeri.in');
        reset(f1);
        assign(f2,'stergeri.out');
        rewrite(f2);
        read(f1,n,m,k);
        for i:=1 to m do
                read(f1,v1[i],v2[i]);
        for i:=m downto 1 do
                if k>=v1[i] then
                        k:=k+v2[i]-v1[i]+1;
        writeln(f2,k);
        close(f1);
        close(f2);
end.