/**************************************************************

    Problem:

    User: BLADEVIL

    Language: Pascal

    Result: Accepted

    Time: ms

    Memory: kb

****************************************************************/

 

//By BLADEVIL

var

    x, y                            :extended;

    n                               :longint;

     

function max(a,b:extended):extended;

begin

    if a>b then max:=a else max:=b;

end;

 

function min(a,b:extended):extended;

begin

    if a>b then min:=b else min:=a;

end;

 

function dfs(x,y:extended;n:longint):extended;

var

    ans, r                          :extended;

    i                               :longint;

begin

    if x>y then

    begin

        ans:=x; x:=y; y:=ans;

    end;

    if n= then exit(y/x);

    r:=/n; ans:=1e20;

    for i:= to n- do

    begin

        ans:=min(ans,max(dfs(x*r*i,y,i),dfs(x-x*r*i,y,n-i)));

        ans:=min(ans,max(dfs(x,y*i*r,i),dfs(x,y-y*r*i,n-i)));

    end;

    exit(ans);

end;

 

 

begin

    read(x,y,n);

    writeln(dfs(x,y,n)::);

end.