#P2942. [USACO09MAR] Moon Mooing G
[USACO09MAR] Moon Mooing G
Description
A full moon casts some sort of spell on the cows and, like their cousins the wolves and coyotes, they bay at the moon — mooing instead of howling, of course.
Each "moo" lasts a certain amount of time. A short "moo" might last time 1; a longer one might last time 24 or even 1,000,000,000 or longer (cows can really moo when they want to). No "moo" will last more than or equal to .
It should come as no surprise that the cows have a pattern to their moos. Bessie will choose an integer () that is the initial length of a moo.
After Bessie moos for length , the cows calculate times for subsequent moos. They apply two formulae to each moo time to yield even more moo times. The two formulae are:
f1(c)=a1*c/d1+b1 (integer divide, of course) and
f2(c)=a2*c/d2+b2.
They then successively use the two new times created by evaluating f1(c) and f2(c) to create even more mooing times. They keep a sorted list of all the possible mooing times (discarding duplicates).
They are allowed to moo a total of N times (1 <= N <= 4,000,000). Please determine the length of the longest moo before they must quit.
The constants in the formulae have these constraints: 1 <= d1 < a1; d1 < a1 <= 20; 0 <= b1 <= 20; 1 <= d2 < a2; d2 < a2 <= 20; 0 <= b2 <= 20.
Consider an example where c=3 and N=10. The constants are:
a1=4 b1=3 d1=3
a2=17 b2=8 d2=2
The first mooing time is 3, given by the value of . The total list of mooing times is:
1. c=3 -> 3 6. f2(3)=17*3/2+8 -> 33
2. f1(3)=4*3/3+3 -> 7 7. f1(28)=4*28/3+3 -> 40
3. f1(7)=4*7/3+3 -> 12 8. f1(33)=4*33/3+3 -> 47
4. f1(12)=4*12/3+3 -> 19 9. f1(40)=4*40/3+3 -> 56
5. f1(19)=4*19/3+3 -> 28 10. f1(47)=4*47/3+3 -> 65
The tenth time is 65, which would be the proper answer for this set of inputs.
They keep a sorted list of all possible moo times (discarding duplicates). They are allowed to moo a total of times (). Please determine the length of the -th moo.
The constants in the formulae are integers and satisfy: ; ; ; .
The two formulae are: .
Input Format
- Line 1: Two space-separated integers: and .
- Line 2: Three space-separated integers: , , and .
- Line 3: Three space-separated integers: , , and .
Output Format
- Line 1: A single integer — the length of the -th moo.
3 10
4 3 3
17 8 2
65
Hint
Translated by ChatGPT 5
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