为什么程序不能从洛谷上通过？

[codep]program p2114;
var n,m,now,max,min,po,i:longint;
    mt,st,bt:array[1..33] of boolean;
    s:ansistring;
begin
    fillchar(mt,sizeof(mt),false);
    fillchar(st,sizeof(st),false);
    readln(n,m);
    min:=0;
    for i:=1 to 31 do
    if ((1 shl i)-1)>=m then break;
    max:=(1 shl i)-1;
    for i:=1 to n do
    begin
        readln(s);
        if s[1]='A' then
        begin
            val(copy(s,5,length(s)-4),now,po);
            max:=max and now;
            min:=min and now;
        end
        else
        if s[1]='O' then
        begin
            val(copy(s,4,length(s)-3),now,po);
            max:=max or now;
            min:=min or now;
        end
        else
        if s[1]='X' then
        begin
            val(copy(s,5,length(s)-4),now,po);
            max:=max xor now;
            min:=min xor now;
        end;
    end;
    for i:=0 to 30 do
    begin
        if (max and (1 shl i))<>0 then mt[i+1]:=true;
        if (min and (1 shl i))<>0 then st[i+1]:=true;
    end;
    now:=0;
    po:=0;
    for i:=31 downto 1 do
        if st[i] then now:=now+(1 shl(i-1))
        else
        if (mt[i])and((po+(1 shl(i-1)))<=m) then
        begin now:=now+(1 shl(i-1));po:=po+(1 shl(i-1));end;
    writeln(now);
end.[/codep]