var n,m,i,j,k:longint;

s:string;

s1:array[0..1000] of int64;

a,f:array[0..1000,0..1000] of int64;

begin

readln(n,m);

readln(s);

for i:=1 to length(s) do s1[i]:=ord(s[i])-48;

for i:=1 to n do begin

a[i,i]:=s1[i];

for j:=i+1 to n do a[i,j]:=a[i,j-1]*10+s1[j];

end;

for i:=1 to n do f[i,0]:=a[1,i];

for i:=2 to n do for j:=1 to m do for k:=1 to i-1 do

if f[i,j]<f[k,j-1]*a[k+1,i] then f[i,j]:=f[k,j-1]*a[k+1,i];

writeln(f[n,m]);

end.