//By BLADEVIL

var

    n, m                    :longint;

    pre, other              :array[..] of longint;

    last                    :array[..] of longint;

    h                       :array[..] of longint;

    max                     :longint;

    vis                     :array[..] of boolean;

    l                       :longint;

    ans                     :longint;

procedure connect(x,y:longint);

begin

    inc(l);

    pre[l]:=last[x];

    last[x]:=l;

    other[l]:=y;

end;

procedure init;

var

    i, x, y, z              :longint;

begin

assign(input,'ski.in'); reset(input);

assign(output,'ski.out'); rewrite(output);

    read(n,m);

    max:=; l:=;

    for i:= to n do

    begin

        read(h[i]);

        if h[i]>h[max] then max:=i;

    end;

    for i:= to m do

    begin

        read(x,y);

        connect(x,y);

    end;

end;

procedure dfs(x:longint);

var

    p, q                    :longint;

begin

    q:=last[x];

    if q= then

    begin

        inc(ans);

        exit;

    end;

    while q<> do

    begin

        p:=other[q];

        if not vis[p] then

        begin

            vis[p]:=true;

            dfs(p);

            vis[p]:=false;

        end;

        q:=pre[q];

    end;

end;

begin

    init;

    dfs(max);

    writeln(ans);

close(input); close(output);

end.