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anyone take LSAT today

anyone take LSAT today# Law - 律师事务所

c*y2010-06-07 07:06

1 楼

Quantitative Portfolio manager
CITIC Securities, a leading securities house in China, is looking for
experienced individuals who will develop and implement quantitative
strategies in China and other equity markets.
Department: Equities & Derivatives Trading.
Position: Executive Director / Director
Number: 1-2
Location: Beijing, China
Preferred strategies: high frequency to short-term trading strategies;
statistical arbitrage;
Responsibilities:
- Strategy design and investment management
- Develop high frequency and short-term equity trading strategies
- Develop statistical arbitrage strategies.
Requirements:
- At least 5 years experience in quantitative strategy design or portfolio
management in hedge funds or proprietary trading desks in investment banks
- Master's degree or above.
- Fluency in Chinese and English
Skills:
- Excellent in quantitative investment and portfolio management
- Excellent skills in econometrics and statistics
- Familiar with MATLAB or C++ programming
Interested candidates please send resume to Email: x*[email protected]
For information about CITIC Securities, please visit http://www.ecitic.com

e*w2010-06-07 07:06

2 楼

原来以为是一个小伤口结的痂，快一个星期了，一直快掉不掉的。今天仔细看，才看到
是只有八只脚的小蜘蛛，拔出来的时候有些疼，这只蜘蛛现在还活着，被我放到小瓶子
里了。不知道这只昆虫怎么会跑到左腹部皮肤里。这只蜘蛛很小，小瓜子型，黑褐色，
直径大约3毫米。腿不是很长，跟身体长度差不多。有哪位知道这种情况的，要不要紧
？

j*b2010-06-07 07:06

3 楼

看看是哪里照的
提示：所有的照片都是在美国拍的

h*b2010-06-07 07:06

4 楼

class Foo {
public:
virtual ~Foo() {}
};
class Bar : public Foo {
};
class Bar2 : public Foo {
};
class FooBar : public Bar {
};
class FooBar2 : public Bar2 {
};
以下哪个对？
1. Foo &foo = static_cast(FooBar2 f);
2. Foo &foo = dynamic_cast(*(new FooBar2)); 编译不过。
2肯定对，为啥1不对？我试了，如果1写成，
FooBar2 1；
Foo &foo = static_cast(f);
编译没问题。
指教，谢谢

h*s2010-06-07 07:06

5 楼

How do you feel? I have a LR as an experiment. out of three LRs, one is
quite easy, I finished with 5 min to spare. the other two I only have 1 min
left. Unfortunately seems the easy one is the experiment :(

h*q2010-06-07 07:06

6 楼

顶

e*w2010-06-07 07:06

7 楼

补充：不痛不痒。有一点点红。

S*t2010-06-07 07:06

8 楼

hoover dam and las vegas :)

h*82010-06-07 07:06

9 楼

有没有可能是因为Foo &foo = static_cast(FooBar2 f) 中的f在cast完以后就
生命结束了，这样foo是一个无效地址的引用，所以不可以
而FooBar2 f；
Foo &foo = static_cast(f);
中f还是有效的，所以编译通过了

A*r2010-06-07 07:06

10 楼

最简单的应该是实验部分，我也是不到30m就做完了，是第五个section.
就是可怜RC又没有全做完，哭啊

min

【在 h*s 的大作中提到】

: How do you feel? I have a LR as an experiment. out of three LRs, one is
: quite easy, I finished with 5 min to spare. the other two I only have 1 min
: left. Unfortunately seems the easy one is the experiment :(

g*j2010-06-07 07:06

11 楼

Are you sure that it is a spider, not louse, scabie or tick? You can take a
picture of the bug and post it online.

p*e2010-06-07 07:06

12 楼

第二张难道不是纽约吗?

【在 S*******t 的大作中提到】

: hoover dam and las vegas :)

z*e2010-06-07 07:06

13 楼

1. static_cast(FooBar2 f)
FooBar2 f; is a "statement", not a "variable".
if you need something should be like this:
const Foo& foo=static_cast(FooBar2());
i guess hhxk18 means the above.

h*s2010-06-07 07:06

14 楼

The 5th section should be the scored one. Experimental section is usually
among the first 3 sections.

【在 A********r 的大作中提到】

: 最简单的应该是实验部分，我也是不到30m就做完了，是第五个section.
: 就是可怜RC又没有全做完，哭啊
:
: min

e*w2010-06-07 07:06

15 楼

谢谢，我查了一下，应该是tick. 我家没有狗，不知道从哪里传上的。有点怕怕。估计
在身上呆了一个星期了，要不要去医院检查一下。谢谢，你的知识真渊博。不说，我还
真不知道是什么。

M*82010-06-07 07:06

16 楼

黯然爬走。。。。

【在 p******e 的大作中提到】

: 第二张难道不是纽约吗?

h*82010-06-07 07:06

17 楼

啊你说的对

【在 z****e 的大作中提到】

: 1. static_cast(FooBar2 f)
: FooBar2 f; is a "statement", not a "variable".
: if you need something should be like this:
: const Foo& foo=static_cast(FooBar2());
: i guess hhxk18 means the above.

g*r2010-06-07 07:06

18 楼

if it's a tick, then you really need to go see your doctor, bring the tick
with you so they can send it to lab to identify it,
you will likely need to have to take doxycycline 200mg for prophylaxis since
you think it has been attached to you for more than a week, and if it's an
adult deer tick,
you could also got it from any recent camping or wilderness exploration,

【在 e*w 的大作中提到】

: 谢谢，我查了一下，应该是tick. 我家没有狗，不知道从哪里传上的。有点怕怕。估计
: 在身上呆了一个星期了，要不要去医院检查一下。谢谢，你的知识真渊博。不说，我还
: 真不知道是什么。

T*r2010-06-07 07:06

19 楼

看比例，不像

【在 p******e 的大作中提到】

: 第二张难道不是纽约吗?

J*n2010-06-07 07:06

20 楼

我印象中，如果不是buildin type,static_cast只能对指针进行操作吧。

【在 h****b 的大作中提到】

: class Foo {
: public:
: virtual ~Foo() {}
: };
: class Bar : public Foo {
: };
: class Bar2 : public Foo {
: };
: class FooBar : public Bar {
: };

g*j2010-06-07 07:06

21 楼

Gomer is absolutely right. You got to be very careful about ticks because
they carry several terrible infectious microbes.

j*b2010-06-07 07:06

22 楼

牛！不过我觉得拍还是很好地，特别是那个坝：可以看出水在流，而天空完全静止。
而者的颜色一样，也就完成了静与动的结合

【在 S*******t 的大作中提到】

: hoover dam and las vegas :)

t*t2010-06-07 07:06

23 楼

印象不对.

【在 J*****n 的大作中提到】

:
: 我印象中，如果不是buildin type,static_cast只能对指针进行操作吧。

g*r2010-06-07 07:06

24 楼

learned the lesson in a hardway, had a young patient admitted with fever and
abnormal liver function test that we all thought was cholecystitis or some
sort biliary infection/inflammation, he quickly deterioated into multi-organ
failure and died, postmorterm showed babesiosis,
though lyme disease is all people talking about, i've yet to see one,

【在 g*****j 的大作中提到】

: Gomer is absolutely right. You got to be very careful about ticks because
: they carry several terrible infectious microbes.

c*l2010-06-07 07:06

25 楼

女神手里咋不拿副扑克牌亚？

【在 S*******t 的大作中提到】

: hoover dam and las vegas :)

h*u2010-06-07 07:06

26 楼

g++ 3.4.4
FooBar2 f;
Foo& foo=static_cast(f);
通过
Foo& foo=static_cast(FooBar2());
通不过
const Foo& foo=static_cast(FooBar2());
通过
谁给讲讲第二个为什么通不过？

【在 z****e 的大作中提到】

: 1. static_cast(FooBar2 f)
: FooBar2 f; is a "statement", not a "variable".
: if you need something should be like this:
: const Foo& foo=static_cast(FooBar2());
: i guess hhxk18 means the above.

j*n2010-06-07 07:06

27 楼

中国有同样景观

【在 c*l 的大作中提到】

: 女神手里咋不拿副扑克牌亚？

d*p2010-06-07 07:06

28 楼

What's the point to get reference of a temporary?
This will fail in vritually all compilers except vs.

【在 h*******u 的大作中提到】

: g++ 3.4.4
: FooBar2 f;
: Foo& foo=static_cast(f);
: 通过
: Foo& foo=static_cast(FooBar2());
: 通不过
: const Foo& foo=static_cast(FooBar2());
: 通过
: 谁给讲讲第二个为什么通不过？

c*l2010-06-07 07:06

29 楼

那个可能拿的是毛主席语录。

【在 j******n 的大作中提到】

: 中国有同样景观

d*p2010-06-07 07:06

30 楼

The third one is only syntactically right : converting a temporary into a r-
value is ok.
But it is a programming error.

【在 h*******u 的大作中提到】

a*a2010-06-07 07:06

31 楼

第一张很好看！感觉那个房子好雄伟，都比山还高了：）

h*u2010-06-07 07:06

32 楼

先不提临时变量,问题是为什么第三个语义上对，而第二个编译却不通过.const区别在
哪里.

【在 d****p 的大作中提到】

: The third one is only syntactically right : converting a temporary into a r-
: value is ok.
: But it is a programming error.

S*t2010-06-07 07:06

33 楼

嗯，照片拍的很好，看出las vegas 完全是因为后面的建筑：）

【在 j*****b 的大作中提到】

: 牛！不过我觉得拍还是很好地，特别是那个坝：可以看出水在流，而天空完全静止。
: 而者的颜色一样，也就完成了静与动的结合

d*p2010-06-07 07:06

34 楼

T const & is r-value so it accepts T
T& is l-value so it rejects T as a temporary.

【在 h*******u 的大作中提到】

: 先不提临时变量,问题是为什么第三个语义上对，而第二个编译却不通过.const区别在
: 哪里.

z*e2010-06-07 07:06

35 楼

什么programming error?
take a const reference of a temporary is a programming error, why?
the reference can be used later on, so why it is an error?

r-

【在 d****p 的大作中提到】

: The third one is only syntactically right : converting a temporary into a r-
: value is ok.
: But it is a programming error.

d*p2010-06-07 07:06

36 楼

I think we are gonna start a tricky discussion :-)
The lifetime of a temporary is ended when the expression generating the
temporary is evaluated.
So,
Foo const& foo = static_cast(Foo()) will yield a dead reference,
pointing to destroyed object (the
foo). Isn't it a programming error?
So never explictly construct a reference to a temporary - doing so will
invalidate the object behind the
reference when the initialization statement completes.
The form DoSthForFoo(Foo()) is valid (supp

【在 z****e 的大作中提到】

: 什么programming error?
: take a const reference of a temporary is a programming error, why?
: the reference can be used later on, so why it is an error?
:
: r-

z*e2010-06-07 07:06

37 楼

so now i see your point that in the function call, temporary lifetime is
determined in the caller's scope.
i totally agree that the temporary will be destroyed after the expression is
evaluated.
But i also expect there are some situations when the temporary will not be
physically destroyed if a reference is attached to it.
sometimes, i tried this kind of coding, and it usually works.
So, if you are sure that the temporary will be destroyed even if there is a
const reference attached to, then i w

【在 d****p 的大作中提到】

: I think we are gonna start a tricky discussion :-)
: The lifetime of a temporary is ended when the expression generating the
: temporary is evaluated.
: So,
: Foo const& foo = static_cast(Foo()) will yield a dead reference,
: pointing to destroyed object (the
: foo). Isn't it a programming error?
: So never explictly construct a reference to a temporary - doing so will
: invalidate the object behind the
: reference when the initialization statement completes.

d*p2010-06-07 07:06

38 楼

OK, could you tell if the following code is OK? What's the value of a in
main()?
class Foo
{
public:
....Foo(int a) : a(a) {}
....int GetValue() { return a; }
private:
....int a;
};
int main()
{
....const Foo& foo = static_cast(Foo(1));
... int a = foo.GetValue();
....return 0;
}

is
a
do

【在 z****e 的大作中提到】

: so now i see your point that in the function call, temporary lifetime is
: determined in the caller's scope.
: i totally agree that the temporary will be destroyed after the expression is
: evaluated.
: But i also expect there are some situations when the temporary will not be
: physically destroyed if a reference is attached to it.
: sometimes, i tried this kind of coding, and it usually works.
: So, if you are sure that the temporary will be destroyed even if there is a
: const reference attached to, then i w

z*e2010-06-07 07:06

39 楼

you may need to have a const member function
int GetValue() const {return a;}
in my machine, the value of 'a' in main is the same as the value of 'a' in the
temporary Foo(x); (assuming the GetValue is a const mem fun.)
so, i mean, i still agree with you that tmp will be destroyed when expression is done the evaluation.
but when there is a const ref attached to the tmp, i'm not quite sure if the tmp will be deleted physically or not.

【在 d****p 的大作中提到】

: OK, could you tell if the following code is OK? What's the value of a in
: main()?
: class Foo
: {
: public:
: ....Foo(int a) : a(a) {}
: ....int GetValue() { return a; }
: private:
: ....int a;
: };

d*p2010-06-07 07:06

40 楼

Good catch - the GetValue() should be const.
So do you think the code is valid? :-)

the

【在 z****e 的大作中提到】

: you may need to have a const member function
: int GetValue() const {return a;}
: in my machine, the value of 'a' in main is the same as the value of 'a' in the
: temporary Foo(x); (assuming the GetValue is a const mem fun.)
: so, i mean, i still agree with you that tmp will be destroyed when expression is done the evaluation.
: but when there is a const ref attached to the tmp, i'm not quite sure if the tmp will be deleted physically or not.

z*e2010-06-07 07:06

41 楼

yes of course, it compiles fine and shows the correct value.

【在 d****p 的大作中提到】

: Good catch - the GetValue() should be const.
: So do you think the code is valid? :-)
:
: the

z*e2010-06-07 07:06

42 楼

when a ref is declared, it must be defined. so the ref is attached to some
piece of memory.
if this piece of memory is destoryed, i think the above code shows "
undefined" behavior even the correct result is shown.
let me try an other snip example to see if my understanding is right or not.

z*e2010-06-07 07:06

43 楼

add this to the code
~Foo(){
cout<}
output
Foo::~Foo()
1
so the result should be "undefined" when const refer to a tmp.
i now agree with you about this point.
thanks for digging this out.

d*p2010-06-07 07:06

44 楼

Cool :-)
Offer letter on the way...

【在 z****e 的大作中提到】

: add this to the code
: ~Foo(){
: cout<: }
: output
: Foo::~Foo()
: 1
: so the result should be "undefined" when const refer to a tmp.
: i now agree with you about this point.
: thanks for digging this out.

z*e2010-06-07 07:06

45 楼

55555555555555555
and hope it can really happen within a year.

【在 d****p 的大作中提到】

: Cool :-)
: Offer letter on the way...

t*t2010-06-07 07:06

46 楼

i think you are wrong here.
the lifetime of a temporary is ended when expression generating the temp is
fully-evaluated, that's usually correct; except in two cases: 1. temp appear
s in the initializer of a declarator, then temp persists until initializatio
n completes. 2. temp is bind to a (const) reference; then temp persists unti
l the reference is out of bound. see 12.2, clause 3-5.

reference,

【在 d****p 的大作中提到】

t*t2010-06-07 07:06

47 楼

however, you are right that your example is not OK. let me make it clear:
const A& = A(); //OK
const A& = static_cast(A()); //wrong
you must bind the temp *directly* to the const reference, then clause 5 is
in effect. if cast with static_cast, then clause 5 is not in effect.

【在 d****p 的大作中提到】

d*p2010-06-07 07:06

48 楼

You are right; thanks for pointing it out.
The static cast expression bypasses the rule for extending temporary's
lifetime: the right side of the initializer
is not a temporary of type T (instead, it is another expression yielding a
const reference const T&). So the
temporary's lifetime is only as long as the expression (in this case the
cast).
Hmmm, a cast sometimes does make a difference.

is

【在 t****t 的大作中提到】

: however, you are right that your example is not OK. let me make it clear:
: const A& = A(); //OK
: const A& = static_cast(A()); //wrong
: you must bind the temp *directly* to the const reference, then clause 5 is
: in effect. if cast with static_cast, then clause 5 is not in effect.

z*e2010-06-07 07:06

49 楼

!!!

is

【在 t****t 的大作中提到】

h*u2010-06-07 07:06

50 楼

顶。几位都是大牛
细节上见高低

is

【在 t****t 的大作中提到】