673 - Parentheses Balance

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turuthok
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Post by turuthok »

Yes.

-turuthok-
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AaronWu
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Post by AaronWu »

Could you show me with a simple example ?(concerning gets(),followed by the atoi() to obtain n...)
Thanks
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turuthok
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Post by turuthok »

Ok, this line shall replace your cin >> n;

gets(chs); n = atoi(chs);

And don't forget to include stdlib.h

-turuthok-
The fear of the LORD is the beginning of knowledge (Proverbs 1:7).

AaronWu
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Post by AaronWu »

Thank you,turuthok. :D
I got AC for it now. But if it is not too bothered, would you mind explaining the reason why the online-judge System refuses to accept my code and how this change of code could be accepted again.
:(
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anupam
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Post by anupam »

you can also use

gets(a);
sscanf(a,"%d",&n);

another very easy method.
"Everything should be made simple, but not always simpler"

AaronWu
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Post by AaronWu »

But what is wrong with the following way to obtain an integer? Aren't they correct?
[cpp]
cin>>n;
or scanf("%d",&n);

[/cpp]
To save time is to lengthen life.

LPH
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Re: 673Parentheses Balance

Post by LPH »

here are part of your code:
AaronWu wrote: [cpp]
cin>>n;
.
.
gets(chs);
[/cpp]
they are correct, but differ from gets(), when you use these two, they will left a '\n' in the input stream('cause they only see the number before it). after then, you use gets(), and it see this '\n' and get it back for the first string, which will be a empty string. since this problem should run when empty string entered, you get "Yes" before your first input every time you run, so it resulted to WA.

using gets() instead of these two method will read in the '\n' (though gets() didn't put it into your string).you can use atoi() or sscanf() to read the number you want from the string just read.

hope these will explain your question :)

anupam
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Post by anupam »

Just debug with the any known debugger with watch window and you can easily find what the problem is to use scanf and gets together. There is space and endline problems with gets and scan used together.
"Everything should be made simple, but not always simpler"

AaronWu
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Post by AaronWu »

Thank you very much indeed.I've never noticed that before :oops:
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Zhao Le
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Post by Zhao Le »

I have occurred to the same question.

I can solve when using
first gets();
then atoi();

but it is C like.

I hate to both include iostream and stdio
my question is how can I turn it to C++ iostream when occurred to the multiply input.
AC makes me feels good,
But WA makes me thinks hard.

Jewel of DIU
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673: WA help plzzzz

Post by Jewel of DIU »

My prog is ok. But i have got wa plz help me.

My Input
[c]7
([])
(([()])))
([()[]()])()
)
()
)(
([)][/c]
My Output
[c]Yes
No
Yes
No
Yes
No
No[/c]

Are my output ok? :cry: :cry: :cry:
Hate WA
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the LA-Z-BOy
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Post by the LA-Z-BOy »

hi, your outputs are okay.
some tricky cases to think of:

Code: Select all

3
()()(((
<blank line>
()())))
output is:

Code: Select all

No
Yes
No
thank you.
Istiaque Ahmed [the LA-Z-BOy]

Jewel of DIU
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Thanx

Post by Jewel of DIU »

Thank u very much for ur help. My program gives Wrong output for ur 1st input. I fixed the prob and got AC.

BTW, I think ur from BUET. Do u know UTTAM? He tells me abt u.
Hate WA
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the LA-Z-BOy
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Post by the LA-Z-BOy »

yah, i'm from BUET. i know UTTAM too.
cheers
Istiaque Ahmed [the LA-Z-BOy]

20717TZ
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673 Accepted but so long time. but I think my algorithm is..

Post by 20717TZ »

673 Accepted but so long time. CPU=0:07.137 My God!!!!!
I think my algorithm is so simple and it should execute quickly, but I am wrong.
Why?
help me plzzzzzzz!

[cpp]
#include <stdio.h>
#include <string>
using namespace std;

int fnBalance(string s)
{
int place;

for(int i=0;s.find("[]")!=-1 || s.find("()")!=-1;i++)
{
while((place=s.find("[]"))!=-1)
s.erase(place,2);
while((place=s.find("()"))!=-1)
s.erase(place,2);
}
return s.length()==0?1:0;
}

void main()
{
FILE* fp=fopen("Input.txt","r");
int n; char c; string s;

fscanf(fp,"%d",&n);
c=fgetc(fp);//fgets(cs,MAX,fp);//skip a '\n'
for(int i=0;i<n;i++)
{
s="";//reset
while((c=fgetc(fp))!='\n' && c!=EOF)
s+=c;
printf("%s\n",fnBalance(s)?"Yes":"No");
}
}
[/cpp]
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