OJ Board

As title, they were disabled on the old server and I can't see any clue in the new interface ..

Thanks for any response,
Hector

Hello I'am a 2-year user

The new server and the new ACM online looks cool but..

when I click "browse problems" and then check about "Volume C"

It spent 1 minutes to wait for the probelmset show, a little too slow, you know.... may be TLE :D




Hope it will be improved : )

thanks

And finally I get Accepted. :D

The bug is that when I implement my Dijkstra's algorithm,

I use "heap" to be a min-priority queue.

And I forget to maintain the min-priority property everytime I make some action to the heap......

It's just a silly mistake....but I think it is easily to be ignored ...

DP:

Take a example, assume there are 5 nodes.

A,B,C,D,E

The program will run five times , k = A to E

for k = A:

Begin with node A , use Dijkstra's to travel the graph
then I get the shortest paths to B,C,D,E
that 4 value will be added to the dist

after k = E done.

=>

dist will store the ...

hi , I read my program again and I found one thing .

does your execution maintain dis(i,i)=0 ?


Yes , I used a matrix to store the graph and set all graph [j] = 0
So if there is no input about house I to house J , the distance between them will be zero.(not connected ...

My prog outputs the same..

any other inputs~? plz >"<

I tried to solve this problem with Dijkstra's Algorithm N times.
(I know there is a better way.... but I just try it...)

But WA so many times, can anyone send me some critical test cases?

I've read the previous posts already.

btw,

Will the following output appears?


3 1
Hector
John
Ray
2 3 1 ...

My algorithm is to create a "stack" ,
and required permutation stored in a array named "permutation"
After input,
I check number 1 to N in a for loop
if number i entered now and the permutation need him now,
the permutation index changes to the next index and check if there are other can be pop ...

Just

Ans = 1 + C(n,2) + C(n,4)

-> 1 + n*(n-1)/2 + n*(n-1)*(n-2)*(n-3)/24

------

We can observe and get it.

When n = 1 , ans = 1;
1 is the original area.

When n = 2 , ans = 2;
We have two points so get 1 line.Just add 1 more area.

When n = 3 , ans = 4;
We have three points so get 3 lines,Just ...

Got AC.

The judge is too tricky......

even a unknown float mistake can cause (WA)^n

~"~

Here is the code


/*Use b-search,or the bisection method to find the answer*/
#include<cstdio>
#include<cmath>
using namespace std;
double x,y,c,s,func,U,D,e,f;
int main(void)
{
while(scanf("%lf%lf%lf",&x,&y,&c)==3)
{
if(x==y&&c!=0)
{
s = sqrt(x*x-4*c*c);
printf("%.3lf\n",s);
}
else if(c ...

Sorry,

the title is find the "bug" , not the "big" |||

/________________________\

Here is my code

Will some function like sqrt() make errors or I miss any part here?

Please tell me , thanks a lot. ^^

#include<cstdio>
#include<cmath>
using namespace std;
int prime=0;
int judge(int a,int b);
int main(void)
{
int N,n[50];
double pi;
while(scanf("%d",&N)==1)
{
if(N==0 ...