var
n,m,i,r1,r2,x,y,q,max,s,j,t:longint;
f,g:array[1..30000]of longint;
function find(x:longint):longint;
var
root:longint;
begin
if(f[x]=x) then find:=x else begin
f[x]:=find(f[x]);find:=f[x];end;
end;
begin
readln(n,m);
for i:=1 to n do f[i]:=i;
for i:=1 to n do g[i]:=1;
for i:=1 to m do
begin
readln(x,y);if x>y then begin t:=x;x:=y;y:=t;end;
r1:=find(x);r2:=find(y);
if r1<>r2 then begin f[r2]:=r1;g[r1]:=g[r1]+g[r2];end;
end;
max:=0;
for i:=1 to n do
if g[i]>max then max:=g[i];
writeln(max);
end.