## 10491 - Cows and Cars

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titid_gede
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Joined: Wed Dec 11, 2002 2:03 pm
Location: Mount Papandayan, Garut

### 10491 - Cows and Cars

how to solve this problem? looks easy but i didnt get it.
Kalo mau kaya, buat apa sekolah?

Red Scorpion
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Joined: Sat Nov 30, 2002 5:14 am
Yes, this is an easy problem, try to think about possibilities.

mido
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Location: Cairo,Egypt
Quite easy, but can get very annoying. To solve it, I thought about the probabilities of the paths one might take in each case. This helped me get to the solutions presented in the sample output. Continue thinking from there....

titid_gede
Experienced poster
Posts: 187
Joined: Wed Dec 11, 2002 2:03 pm
Location: Mount Papandayan, Garut
Yes, look easy but very annoying me. e.g for input 2 1 1. there are 3 doors, which two of them contains cows. so first the probability of getting cars is 1/3. then a door which contained cow opened. here i saw that probability of getting car if i change the choice is 0.5. since i know there is only one car and one cow, it's fifty fifty. or my analysis is wrong?
Kalo mau kaya, buat apa sekolah?

titid_gede
Experienced poster
Posts: 187
Joined: Wed Dec 11, 2002 2:03 pm
Location: Mount Papandayan, Garut
forget it, now i got AC. i read problem carefully, and find what i missed.
Kalo mau kaya, buat apa sekolah?

Shr33
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Joined: Mon May 26, 2008 4:51 pm

### Re: 10491 - Cows and Cars

i do a mistake S0 PLS ,
i wanna specify that all shows are done at a single time
NOTTTT one by oneeee okkkk

S0 THIS IS EASY QUESTION DONT THINK DIFFERENT TAKE IT EASY

898989
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### Re: 10491 - Cows and Cars

I still can not figure out how to solve it. Can any one gives more explanation.
Sleep enough after death, it is the time to work.

stcheung
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### Re: 10491 - Cows and Cars

Consider these 2 scenarios:
(1) Cow was initially chosen, then a Car was chosen after doors are revealed
(2) Car was initially chosen, then a Car was chosen after doors are revealed

The result is the sum of their probabilities.

codeworrior
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Joined: Wed Oct 21, 2009 11:04 am

### Re: 10491 - Cows and Cars

whats the problem in my code..its giving me WA ...is tht scanf line is correct????
Last edited by codeworrior on Wed Oct 28, 2009 12:00 pm, edited 1 time in total.

Taman
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Posts: 32
Joined: Sun Oct 11, 2009 8:59 pm
Location: Southeast University

### Re: 10491 - Cows and Cars

@codeworrior:
try double data type instead of float. . .and it should work. . .

codeworrior
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Joined: Wed Oct 21, 2009 11:04 am

### Re: 10491 - Cows and Cars

thnx buddy...done now..bt wats d problem with float ..i think i was within range and precision was also ok...

Taman
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Posts: 32
Joined: Sun Oct 11, 2009 8:59 pm
Location: Southeast University

### Re: 10491 - Cows and Cars

Ok, simply I can quote Shahriar Manzoor, "It is always a good idea to use double instead of float because double gives higher precision and range.Sometimes it is specified in the problem statement to use float type. In those cases, use floats."

Taman
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Location: Southeast University

### Re: 10491 - Cows and Cars

@Codeworrior: As u are done by now, plz remove your code as early as possilbe. . .thnx

mak(cse_DU)
Learning poster
Posts: 72
Joined: Tue May 30, 2006 5:57 pm

### Re: 10491 - Cows and Cars

!!!!!!!!!!!!!!!!!!
With adding eps=1e-8 gave me WA.
With discarding this eps I got AC.
Surprise.
Mak
Help me PLZ!!

Shafaet_du
Experienced poster
Posts: 147
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### Re: 10491 - Cows and Cars

You dont need eps.
input:

Code: Select all

``````100 100 12
10 10 9
5 5 2
1 1 0
34 64 24``````
output:

Code: Select all

``````0.53209
0.95000
0.64286
0.50000
0.86777``````
best of luck!