Codeforces Round 955 (Div. 2, with prizes from NEAR!)
C
Boring Day
Codeforces
1200
原题
← BD →
翻译中…

On another boring day, Egor got bored and decided to do something. But since he has no friends, he came up with a game to play.

翻译中…

Egor has a deck of $n$ cards, the $i$-th card from the top has a number $a_i$ written on it. Egor wants to play a certain number of rounds until the cards run out. In each round, he takes a non-zero number of cards from the top of the deck and finishes the round. If the sum of the numbers on the cards collected during the round is between $l$ and $r$, inclusive, the round is won; otherwise, it is lost.

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Egor knows by heart the order of the cards. Help Egor determine the maximum number of rounds he can win in such a game. Note that Egor is not required to win rounds consecutively.

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Input

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Each test consists of several test cases. The first line contains an integer $t$ ($1 \le t \le 10^{4}$) — the number of test cases. This is followed by a description of the test cases.

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The first line of each test case contains three integers $n$, $l$, and $r$ ($1 \le n \le 10^{5}$, $1 \le l \le r \le 10^9$).

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The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ($1 \le a_i \le 10^9$) — the numbers on the cards from top to bottom.

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It is guaranteed that the sum of $n$ for all test cases does not exceed $2 \cdot 10^{5}$.

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Output

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For each test case, output a single number — the maximum number of rounds Egor can win.

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Note

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In the first test case, Egor can win $3$ rounds:

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  • In the first round, take the top $2$ cards with values $2$ and $1$ and win, as their sum is $3$. After this, the deck will look like this: $[11, 3, 7]$.
  • In the second round, take the top card and lose, as its value $11$ is greater than $r = 10$. After this, the deck will look like this: $[3, 7]$.
  • In the third round, take the top card with value $3$ and win. After this, the deck will look like this: $[7]$.
  • After this, in the fourth round, Egor only has to take the last card in the deck with value $7$ and win again.
翻译中…

In the second test case, Egor cannot win any rounds, no matter how hard he tries.

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In the third test case, you can take one card in each round, then the first and third rounds will be losing, and the second round will be winning.

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In the fourth test case, you can take two cards in each round and always win.

翻译中…

样例

Input #1
8
5 3 10
2 1 11 3 7
10 1 5
17 8 12 11 7 11 21 13 10 8
3 4 5
3 4 2
8 12 25
10 7 5 13 8 9 12 7
2 3 3
5 2
9 7 9
2 10 5 1 3 7 6 2 3
1 8 10
9
5 5 6
1 4 2 6 4
Output #1
3
0
1
4
0
3
1
2
InputCopy OutputCopy
题目信息
题号
1982C
时间限制
2 s
内存限制
256 MB
标签
二分
数据结构
动态规划
贪心
双指针

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。