497 - Strategic Defense Initiative

[roticv]

The code looks okay to me, but is your SIZE big enough? I used 15000.

[sunny]

pls help me why TLE :

/*
REMOVED
*/

[Jan]

Code: Select all

scanf("%ld%c%*c",&c,&h);

Why you are using variable 'h'? There is no need to use it. Use..

Code: Select all

scanf("%ld",&c);

Hope it helps.

[shalinmangar]

Your code is wrong. Consider the following testcase:

100
45
46
47
48
49
11
1

Your code gives the answer as:
Max hits: 1
1

But actually we can have:
Max hits: 5
45
46
47
48
49

[taskin]

can anyone tell me why its wa.

deleted after ac

[Staryin]

removed

[dumb dan]

Two things that might cause you problems:

char c,snum[5];
5 might be too low. Try changing it to 10 (you want to be able to read numbers that would fit into a 32-bit int).

Also, you print an extra blank line after the last case, which might cause a presentation error.

[Staryin]

THANKS! AC!

[dumb dan]

No problem.

You should probably remove your code now (it's custom to remove ones code after getting AC).

[smilitude]

Well, I couldn't get it to accept until I fixed the zero case... maybe it was just me..

Hehehe! its not only you larry! I also had the same problem, and it costed me three consecutive WAs before getting that zero case idea!

Thanks a lot to everyone!

[Tanu]

I'm trying to solve it in nlog(n) time ...
here is my code...
Plz help...

Code: Select all

#include<stdio.h>
#include<string.h>
#define inf 4294967295
#define MAX 1000000
unsigned long res[MAX],in[MAX];
long top;
long binarySearch(unsigned long key )
{
	long low = 0;
	long high = top- 1;	//zero based array
	long middle;
	
	while( low <= high )
	{
		middle = ( low  + high ) / 2;
		
		if( key == res[  middle ] ) //match
			return middle;
		else if( key < res[ middle ] )
			high = middle - 1;		//search low end of array
		else
			low = middle + 1;		//search high end of array
	}
	return middle;
}


main()
{
	long test = 0,testcase;
	long i,t;
	long pos,k;
	char ss[100];
	//freopen("c:\\in.txt","r",stdin);
	scanf("%ld",&testcase);
	getchar();
	gets(ss);

	while(1)
	{
		if(test == testcase)
			break;
		while(gets(ss))
		{
			if(strcmp(ss,"")==0)
				break;
			res[top] = inf;
			sscanf(ss,"%lu",&in[top++]);
		}
		res[top] = inf;
		k = 0;
		for(t = 0; t < top ;t++)
		{
			pos = binarySearch(in[t]);
			if(res[pos] > in[t])
				res[pos] = in[t];
			else
				res[pos+1] = in[t];
		}
		for(t = 0; t < top ;t++)
			if(res[t] == inf)
				break;
		printf("Max hits: %ld\n",t);
		for(i = 0; i < t ;i++)
			printf("%lu\n",res[i]);
		test++;
		top = 0;
	}
	return 0;
}

There is another question what is the real array size should be declared...
Thanx in advance..
..Tanu

[IRA]

to Tanu:
I try your program....
I find this case
------------------------------------------------
1

10
9
2
3
8
1
-----------------------------------------------
your output:
Max hits:3
1
3
8
-----------------------------------------------
This is not correct.

This problem can solve in O(n^2) use LCS method to find LIS.
I search many web.Can't find O(nlogn) method how to find the correct subsequence.But,it can find correct length.
Q481 need use O(nlogn) method.The problem I have not solve....

[Tanu]

I know the N^2 algorithm...
I'm trying to do it in nlog(n) time...
I learn it from my friend but my code is so useful to make it implemented...
help anyone to solve this problem in better...
Is there any post about it...
Referrence is needed...
Thanx dear IRA...
...Tanu

[smilitude]

Your algorithm is quite right tanu, though it could be more simpler if you used lower_bound of stl. But you have to have a recursive function call to print the LIS. The problem with this nlogk algo is, it always tracks the last element, but not the perfect array it saves.. for that input your code is showing

1
3
8

that is supposed to be

2
3
8

your one is just right... just have another array, that will save which one was on before that - i mean each one will have one parent. Then you have to do a recursive call from the end to print the LIS. [/code]

[algoJo]

Hi, can someone check this I/O set:

INPUT

Code: Select all

11

1 
2 
3 
4 
5 

5 
4 
3 
2 
1 

1 



1 
3 
4 
2 
5 
6

100 
45 
46 
47 
48 
49 
11 
1

1
6
2
3
5

3
2

10

1 
3 
4 
2 
5 
6

OUTPUT

Code: Select all

Max hits: 5
1
2
3
4
5

Max hits: 1
1

Max hits: 1
1

Max hits: 0

Max hits: 0

Max hits: 5
1
3
4
5
6

Max hits: 5
45
46
47
48
49

Max hits: 4
1
2
3
5

Max hits: 1
2

Max hits: 1
10

Max hits: 5
1
3
4
5
6

can someone post more I/O set..
Thanks [/quote]