问题何在？
###Block code
var n,m,k,x,ans:longint;
function fastmi(a,b,c:int64):int64;
begin
fastmi:=1;
a:=a mod c;
while b>0 do
begin
if b mod 2=1 then fastmi:=fastmi*a mod c;
b:=b div 2;
a:=(a*a) mod c;
end;
end;
begin
assign(input,'circle.in'); assign(output,'circle.out');
reset(input); rewrite(output);
readln(n,m,k,x);
ans:=((((m mod n)*(fastmi(10,k,n))) mod n) + x) mod n;
writeln(ans);
end.