EPIC Institute of Technology Round August 2024 (Div. 1 + Div. 2)
F1
Court Blue (Easy Version)
Codeforces
2600
原题
← EF2 →
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This is the easy version of the problem. In this version, $n=m$ and the time limit is lower. You can make hacks only if both versions of the problem are solved.

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In the court of the Blue King, Lelle and Flamm are having a performance match. The match consists of several rounds. In each round, either Lelle or Flamm wins.

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Let $W_L$ and $W_F$ denote the number of wins of Lelle and Flamm, respectively. The Blue King considers a match to be successful if and only if:

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  • after every round, $\gcd(W_L,W_F)\le 1$;
  • at the end of the match, $W_L\le n, W_F\le m$.
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Note that $\gcd(0,x)=\gcd(x,0)=x$ for every non-negative integer $x$.

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Lelle and Flamm can decide to stop the match whenever they want, and the final score of the performance is $l \cdot W_L + f \cdot W_F$.

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Please help Lelle and Flamm coordinate their wins and losses such that the performance is successful, and the total score of the performance is maximized.

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Input

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The first line contains an integer $t$ ($1\leq t \leq 10^3$) — the number of test cases.

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The only line of each test case contains four integers $n$, $m$, $l$, $f$ ($2\leq n\leq m \leq 2\cdot 10^7$, $1\leq l,f \leq 10^9$, $\bf{n=m}$): $n$, $m$ gives the upper bound on the number of Lelle and Flamm's wins, $l$ and $f$ determine the final score of the performance.

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Unusual additional constraint: it is guaranteed that, for each test, there are no pairs of test cases with the same pair of $n$, $m$.

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Output

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For each test case, output a single integer — the maximum total score of a successful performance.

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Note

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In the first test case, a possible performance is as follows:

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  • Flamm wins, $\gcd(0,1)=1$.
  • Lelle wins, $\gcd(1,1)=1$.
  • Flamm wins, $\gcd(1,2)=1$.
  • Flamm wins, $\gcd(1,3)=1$.
  • Lelle wins, $\gcd(2,3)=1$.
  • Lelle and Flamm agree to stop the match.
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The final score is $2\cdot2+3\cdot5=19$.

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In the third test case, a possible performance is as follows:

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  • Flamm wins, $\gcd(0,1)=1$.
  • Lelle wins, $\gcd(1,1)=1$.
  • Lelle wins, $\gcd(2,1)=1$.
  • Lelle wins, $\gcd(3,1)=1$.
  • Lelle wins, $\gcd(4,1)=1$.
  • Lelle wins, $\gcd(5,1)=1$.
  • Flamm wins, $\gcd(5,2)=1$.
  • Flamm wins, $\gcd(5,3)=1$.
  • Flamm wins, $\gcd(5,4)=1$.
  • Lelle and Flamm agree to stop the match.
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The final score is $5\cdot2+4\cdot2=18$. Note that Lelle and Flamm can stop the match even if neither of them has $n$ wins.

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样例

Input #1
8
3 3 2 5
4 4 1 4
6 6 2 2
7 7 2 3
9 9 9 1
2 2 1 4
5 5 1 4
8 8 6 7
Output #1
19
17
18
33
86
9
24
86
InputCopy OutputCopy
Input #2
1
20000000 20000000 1341 331
Output #2
33439999007
InputCopy OutputCopy
Input #3
2
1984 1984 19 84
9982 9982 44 35
Output #3
204143
788403
InputCopy OutputCopy
题目信息
题号
2002F1
时间限制
3 s
内存限制
512 MB
标签
暴力
DFS 及类似
动态规划
数学
数论

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。