I tried a number of tests, and neither of p,q is very big(Many of them beyond 1000). Maybe there's some mathematical property of the f function?

It is not clear from problem statement, but is true for all tests: B1 >= B2.

Where it is required to subtract C, C is positive.


Edited by author 24.04.2009 15:03

"You may assume that all intermediate values of H and all values of F fit in range [0..100000]"

This should be put to problem statement, rather than to input description. Otherwise claim about periodicity is wrong.

Consider the following sequence:

X1=0, X2=2
A1=0, A2=0, A3=2, A4=0
B1=3, B2=2, C=5

0 2 -1 -2 -4 -8 -16 ... -(2^n) ...

It's not periodic, but all coefficients (as well as initial elements) are non-negative.

What is the maximum value of p?

I have two programs 1st - a right one wich have WA#2
and second - gets AC

if you remove comment you get WA#2
WHY? I realy can't understand, anybody please help me!

struct point
{
    int ID;
    double x,y;
};

int Chet(point a)
{
//    if (a.x > 0 && a.y >=0)
        return 0;
//    if (a.x <=0 && a.y > 0)
//        return 1;
//    if (a.x < 0 && a.y <=0)
//        return 2;
//    if (a.x >=0 && a.y < 0)
//        return 3;
}

inline bool Tr(const point &a, const point &b)
{
    return a.x*b.y-a.y*b.x > 0;
}

inline bool operator < (const point &a, const point &b)
{
    int ca = Chet(a);
    int cb = Chet(b);
    return ca < cb || ca==cb && Tr(a,b);
}

Can someone give me some tests? I got wa on test#6

Although it got AC, but I doubt whether it will give an correct answer on all test... :(

My algo is simply find a large num,assume it is on the cycle,and to find the periods...

I think it exist a maths way......or at least, have a good search method use something like hash and so on...