2024年1月美国计算机奥赛USACO竞赛银奖组问题一——Cowmpetency

Farmer John is hiring a new herd leader for his cows. To that end, he has interviewed N(2≤N≤105) cows for the position. After interviewing the i
th candidate, he assigned the candidate an integer "cowmpetency" score ci
ranging from 1 to C inclusive (1≤C≤109) that is correlated with their leadership abilities.

Because he has interviewed so many cows, Farmer John does not remember all of their cowmpetency scores. However, he does remembers Q (1≤Q<N) pairs of numbers (aj,hj) where cow hj was the first cow with a strictly greater cowmpetency score than cows 1 through aj (so 1≤aj<hjN).

Farmer John now tells you the sequence c1,…,cN (where ci=0 means that he has forgotten cow i's cowmpetency score) and the Q pairs of (aj,hj). Help him determine the lexicographically smallest sequence of cowmpetency scores consistent with this information, or that no such sequence exists! A sequence of scores is lexicographically smaller than another sequence of scores if it assigns a smaller score to the first cow at which the two sequences differ.

Each input contains T (1≤T≤20) independent test cases. The sum of N across all test cases is guaranteed to not exceed 3⋅105.

INPUT FORMAT (input arrives from the terminal / stdin):

The first line contains T, the number of independent test cases. Each test case is described as follows:

First, a line containing N, Q, and C.
Next, a line containing the sequence c1,…,cN (0≤ci≤C).
Finally, Q lines each containing a pair (aj,hj). It is guaranteed that all aj within a test case are distinct.

OUTPUT FORMAT (print output to the terminal / stdout):

For each test case, output a single line containing the lexicographically smallest sequence of cowmpetency scores consistent with what Farmer John remembers, or −1 if such a sequence does not exist.

SAMPLE INPUT:

1
7 3 5
1 0 2 3 0 4 0
1 2
3 4
4 5

SAMPLE OUTPUT:

1 2 2 3 4 4 1

We can see that the given output satisfies all of Farmer John's remembered pairs.
max(c1)=1, c2=2 and 1<2 so the first pair is satisfied
max(c1,c2,c3)=2, c4=3 and 2<3 so the second pair is satisfied
max(c1,c2,c3,c4)=3, c5=4 and 3<4so the third pair is satisfied

There are several other sequences consistent with Farmer John's memory, such as
1 2 2 3 5 4 1
1 2 2 3 4 4 5

However, none of these are lexicographically smaller than the given output.

SAMPLE INPUT:

5
7 6 10
0 0 0 0 0 0 0
1 2
2 3
3 4
4 5
5 6
6 7
8 4 9
0 0 0 0 1 6 0 6
1 3
6 7
4 7
2 3
2 1 1
0 0
1 2
10 4 10
1 2 0 2 1 5 8 6 0 3
4 7
1 2
5 7
3 7
10 2 8
1 0 0 0 0 5 7 0 0 0
4 6
6 9

SAMPLE OUTPUT:

1 2 3 4 5 6 7
1 1 2 6 1 6 7 6
-1
1 2 5 2 1 5 8 6 1 3
-1

In test case 3, since C=1, the only potential sequence is

1 1

However, in this case, cow 2 does not have a greater score than cow 1, so we cannot satisfy the condition.

In test case 5,a1and h1 tell us that cow 6 is the first cow to have a strictly greater score than cows 1 through 4. Therefore, the largest score for cows 1 through 6 is that of cow 6: 5. Since cow 7 has a score of 7, cow 7 is the first cow to have a greater score than cows 1 through 6. So, the second statement that cow 9 is the first cow to have a greater score than cows 1 through 6 cannot be true.

SCORING:

Input 3 satisfies N≤10 and Q,C≤4.
Inputs 4-8 satisfy N≤1000.
Inputs 9-12 satisfy no additional constraints.
Problem credits: Suhas Nagar

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2024年1月美国计算机奥赛USACO竞赛金奖组问题三——Nap Sort

Bessie is trying to sort an array of integers using her own sorting algorithm. She has a pile of N (1≤N≤2⋅105) integers a1,a2,…,aN (1≤ai≤1011) that she will put in a separate array in sorted order. She repeatedly finds the minimum integer in her pile, removes it, and adds it to the end of the array. It takes Bessie p seconds to find the minimum integer in a pile of p integers.

Farmer John instructed some of the other cows in the farm to help Bessie with her task, but they are quite lazy, so Bessie uses that to her advantage. She divides the integers into two piles: Bessie pile and Helper pile. For every integer in Bessie's pile, she performs her algorithm as normal. For every integer in the helper pile, she assigns it to a different helper cow. Farmer John has a large farm, so Bessie can get as many helper cows as she wants. If a helper receives the integer ai, Bessie instructs that cow to nap for ai seconds, and add their integer to the end of the array immediately when they wake up. If Bessie and a helper add an integer to the array at the same time, Bessie's integer will get added first since she is the leader. If more than one helper gets assigned the same integer, they will add copies of that integer to the array at the same time.

Help Bessie divide her integers so that the final array is sorted and the time it takes to sort the array is minimized.

INPUT FORMAT (input arrives from the terminal / stdin):

The first line contains T, the number of independent test cases (1≤T≤10).

Each test case is formatted as follows:

The first line of each test case contains the number of integers N in Bessie's array.

The next line of each test case contains a1,a2,…,aN, the integers that Bessie is sorting. The same integer may appear multiple times.

It is guaranteed that the sum of N over all tests does not exceed 2⋅105.

OUTPUT FORMAT (print output to the terminal / stdout):

For each test case, output the minimum time to sort the array on a new line, if Bessie divides her integers optimally.

SAMPLE INPUT:

4
5
1 2 4 5 100000000000
5
17 53 4 33 44
4
3 5 5 5
6
2 5 100 1 4 5

SAMPLE OUTPUT:

6
15
5
6

In the first example, Bessie can assign 1,2 to helpers and leave 4,5,1011 for herself.

In the second example, the best Bessie can do is sort everything by herself. One division that does *not* work is for Bessie to assign 4 to a helper and the rest to herself because Bessie will end up adding 17 to the array before the helper adds 4
to the array.

In the third example, Bessie can assign all the integers to helpers.

In the fourth example, Bessie can assign 1,4,5 to helpers and leave 2,5,100
to herself.

SCORING:

Input 2: N≤16
Inputs 3-5: N≤150
Inputs 6-8: ∑N≤5000
Inputs 9-11: No additional constraints.

Problem credits: Suhas Nagar

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2024年1月美国计算机奥赛USACO竞赛金奖组问题二——Cowmpetency

Farmer John is hiring a new herd leader for his cows. To that end, he has interviewed N (2≤N≤109) cows for the position. After each interview, he assigned an integer "cowmpetency" score to the candidate ranging from 1
to C(1≤C≤104) that is correlated with their leadership abilities.

Because he has interviewed so many cows, Farmer John has forgotten all of their cowmpetency scores. However, he does remembers Q(1≤Q≤min(N−1,100)) pairs of numbers (ai,hi) where cow hi was the first cow with a strictly greater cowmpetency score than cows 1 through ai (so 1≤ai<hiN).

Farmer John now tells you the Q pairs of (ai,hi). Help him count how many sequences of cowmpetency scores are consistent with this information! It is guaranteed that there is at least one such sequence. Because this number may be very large, output its value modulo 109+7.

INPUT FORMAT (input arrives from the terminal / stdin):

The first line contains N, Q, and C.
The next Q lines each contain a pair (ai,hi). It is guaranteed that all aj are distinct.

OUTPUT FORMAT (print output to the terminal / stdout):

The number of sequences of cowmpetency scores consistent with what Farmer John remembers, modulo 109+7.

SAMPLE INPUT:

6 2 3
2 3
4 5

SAMPLE OUTPUT:

6

The following six sequences are the only ones consistent with what Farmer John remembers:

1 1 2 1 3 1
1 1 2 1 3 2
1 1 2 1 3 3
1 1 2 2 3 1
1 1 2 2 3 2
1 1 2 2 3 3

SAMPLE INPUT:

10 1 20
1 3

SAMPLE OUTPUT:

399988086
Make sure to output the answer modulo 109+7.

SCORING:

Inputs 3-4 satisfy N≤10 and Q,C≤4.
Inputs 5-7 satisfy N,C≤100.
Inputs 8-10 satisfy N≤2000 and C≤200.
Inputs 11-15 satisfy N,C≤2000.
Inputs 16-20 satisfy no additional constraints.
Problem credits: Suhas Nagar

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2024年1月美国计算机奥赛USACO竞赛金奖组问题一——Walking in Manhattan

Farmer John and his Q(1≤Q≤2⋅105) cows are in Manhattan on vacation, but the cows have escaped and are now walking around freely in the city! Manhattan is huge – so huge that its N (1≤N≤2⋅105) roads stretch infinitely in the x-y plane, but conveniently, those roads all run perfectly horizontally or vertically. Each horizontal and vertical road can be modeled by an equation of the form y= ci or x=ci , where cis an integer in the range 0 to 109 inclusive.

Farmer John knows exactly where each cow started walking and how long ago they escaped. Cows are very predictable, so each of them walks according to the following pattern:

They only walk north (+y) or east (+x) at one unit per second.
If they are currently on a single road, they continue walking along the road's direction.
If they are at the intersection of two roads, they walk north if they have been walking for an even number of seconds and east otherwise.

Given the layout of Manhattan and the information for each cow, help Farmer John determine where his cows are now!

INPUT FORMAT (input arrives from the terminal / stdin):

The first line contains N and Q.

The next N lines describe the roads. Each road is described by a direction (H or V) and a coordinate ci. It is guaranteed that the roads are unique.

The next Q lines describe the cows. Each cow is described by three integers (xi,yi,di), meaning that they started walking from (xi,yi) exactly di seconds ago. It is guaranteed that (xi,yi) lies on some road, and 0≤xi,yi,di≤109 .

OUTPUT FORMAT (print output to the terminal / stdout):

Output Q lines, where the ith line contains the current position of the ith cow.

SAMPLE INPUT:

4 5
V 7
H 4
H 5
V 6
6 3 10
6 4 10
6 5 10
6 6 10
100 4 10

SAMPLE OUTPUT:

14 5
7 13
6 15
6 16
110 4

The first two cows took the following paths:
(6, 3) -> (6, 4) -> (7, 4) -> (7, 5) -> (8, 5) -> ... -> (14, 5)
(6, 4) -> (6, 5) -> (7, 5) -> (7, 6) -> ... -> (7, 13)

SCORING:
Inputs 2-4 satisfy N,Q,ci,xi,yi,di≤100.
Inputs 5-9 satisfy N,Q≤3000.
Inputs 10-20 satisfy no additional constraints.

Problem credits: Benjamin Qi

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2024年1月美国计算机奥赛USACO竞赛白金组问题三——Mooball Teams III

Farmer John has N cows on his farm (2≤N≤2⋅105), conveniently numbered 1…N
. Cow i is located at integer coordinates (xi,yi) (1≤xi,yi≤N). Farmer John wants to pick two teams for a game of mooball!

One of the teams will be the "red" team; the other team will be the "blue" team. There are only a few requirements for the teams. Neither team can be empty, and each of the N cows must be on at most one team (possibly neither). The only other requirement is due to a unique feature of mooball: an infinitely long net, which must be placed as either a horizontal or vertical line in the plane at a non-integer coordinate, such as x=0.5. FJ must pick teams so that it is possible to separate the teams by a net. The cows are unwilling to move to make this true.

Help a farmer out! Compute for Farmer John the number of ways to pick a red team and a blue team satisfying the above requirements, modulo 109+7.

INPUT FORMAT (input arrives from the terminal / stdin):

The first line of input contains a single integer N.

The next N lines of input each contain two space-separated integers xi and yi. It is guaranteed that the xi form a permutation of 1…N, and same for the yi.

OUTPUT FORMAT (print output to the terminal / stdout):

A single integer denoting the number of ways to pick a red team and a blue team satisfying the above requirements, modulo 109+7.

SAMPLE INPUT:
2
1 2
2 1

SAMPLE OUTPUT:
2
We can either choose the red team to be cow 1 and the blue team to be cow 2, or the other way around. In either case, we can separate the two teams by a net (for example, x=1.5).

SAMPLE INPUT:

3
1 1
2 2
3 3

SAMPLE OUTPUT:

10

Here are all ten possible ways to place the cows on teams; the ith character denotes the team of the ith cow, or . if the ith cow is not on a team.

RRB
R.B
RB.
RBB
.RB
.BR
BRR
BR.
B.R
BBR

SAMPLE INPUT:

3
1 1
2 3
3 2

SAMPLE OUTPUT:

12

Here are all twelve possible ways to place the cows on teams:

RRB
R.B
RBR
RB.
RBB
.RB
.BR
BRR
BR.
BRB
B.R
BBR

SAMPLE INPUT:

40
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
10 10
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 29
30 30
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40

SAMPLE OUTPUT:

441563023

Make sure to output the answer modulo 109+7.

SCORING:

Input 5: N≤10
Inputs 6-9: N≤200
Inputs 10-13: N≤3000
Inputs 14-24: No additional constraints.
Problem credits: Dhruv Rohatgi

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2024年1月美国计算机奥赛USACO竞赛白金组问题二——Merging Cells

**Note: The memory limit for this problem is 512MB, twice the default.**

Bessie is having fun playing a famous online game, where there are a bunch of cells of different labels and sizes. Cells get eaten by other cells until only one winner remains.

There are N (2≤N≤5000) cells in a row labeled 1…N from left to right, with initial sizes s1,s2,…,sN (1≤si≤105). While there is more than one cell, a pair of adjacent cells is selected uniformly at random and merged into a single new cell according to the following rule:

If a cell with label a and current size ca is merged with a cell with label b and current size cb , the resulting cell has size ca +cb and label equal to that of the larger cell, breaking ties by larger label. Formally, the label of the resulting cell is

For each label i in the range 1…N , the probability that the final cell has label i
can be expressed in the form where bi≢0 ( mod 109+7). Output aib−1i ( mod 109+7).

INPUT FORMAT (input arrives from the terminal / stdin):

The first line contains N.
The next line contains s1,s2,…,sN

OUTPUT FORMAT (print output to the terminal / stdout):

The probability of the final cell having label i modulo 109+7
for each i in 1…N on separate lines.

SAMPLE INPUT:

3
1 1 1

SAMPLE OUTPUT:

0
500000004
500000004

There are two possibilities, where (a,b)→c means that the cells with labels a and b merge into a new cell with label c.

(1, 2) -> 2, (2, 3) -> 2
(2, 3) -> 3, (1, 3) -> 3

So with probability 1/2 the final cell has label 2 or 3.

SAMPLE INPUT:

4
3 1 1 1

SAMPLE OUTPUT:

666666672
0
166666668
166666668
The six possibilities are as follows:

(1, 2) -> 1, (1, 3) -> 1, (1, 4) -> 1
(1, 2) -> 1, (3, 4) -> 4, (1, 4) -> 1
(2, 3) -> 3, (1, 3) -> 1, (1, 4) -> 1
(2, 3) -> 3, (3, 4) -> 3, (1, 3) -> 3
(3, 4) -> 4, (2, 4) -> 4, (1, 4) -> 4
(3, 4) -> 4, (1, 2) -> 1, (1, 4) -> 1

So with probability 2/3 the final cell has label 1, and with probability 1/6
the final cell has label 3 or 4.

SCORING:

Input 3: N≤8
Inputs 4-8: N≤100
Inputs 9-14: N≤500
Inputs 15-22: No additional constraints.
Problem credits: Benjamin Qi

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2024年1月美国计算机奥赛USACO竞赛白金组问题一——Island Vacation

Bessie is taking a vacation in a network of N(2≤N≤104) islands labeled 1…N
connected by M bidirectional bridges, each of which connects two islands (N−1≤M≤3/2(N−1)). It is guaranteed that the bridges form a connected simple graph (in particular, no two bridges connect the same pair of islands, and no bridge connects an island to itself).

It is also guaranteed that no bridge lies on more than one simple cycle. A simple cycle is a cycle that does not contain repeated islands.

Bessie starts at island 1, and travels according to the following procedure. Supposing she is currently at island i,

1.If there are no bridges adjacent to island i that she has not yet crossed, she ends her vacation.
2.Otherwise, with probability pi(mod 109+7), she ends her vacation.
3.Otherwise, out of all bridges adjacent to island i that she has not yet crossed, she chooses one uniformly at random and crosses it.

For each island, output the probability that she ends her vacation at that island, modulo 109+7.

INPUT FORMAT (input arrives from the terminal / stdin):

The first line contains the number of independent test cases T (1≤T≤10). Consecutive test cases are separated by an empty line.

The first line of each test contains N and M, where N is the number of islands and M is the number of bridges. It is guaranteed that the sum of N over all test cases does not exceed 104.

The second line of each test contains p1,p2,…,pN (0≤pi<109+7).

The next M lines of each test describe the bridges. The ith line contains integers ui and vi (1≤ui<viN), meaning that the ith bridge connects islands ui and vi. It is guaranteed that the bridges satisfy the constraints mentioned above.

OUTPUT FORMAT (print output to the terminal / stdout):

For each test case, output the probability of ending at each island from 1
to N modulo 109+7 on a single line, separated by spaces.

SAMPLE INPUT:
2

3 2
0 10 111111112
1 3
2 3

6 5
500000004 0 0 0 0 0
1 5
1 3
4 5
5 6
1 2

SAMPLE OUTPUT:

0 888888896 111111112
500000004 166666668 166666668 83333334 0 83333334

For the first test case,p3≡1/9(mod 109+7). Bessie has probability 1/9
of ending at 3(taking the path 1→3) and 8/9of ending at 2(taking the path 1→3→2).

For the second test case, p1 ≡1/2(mod 109+7). Bessie has probability 1/2
of ending at 1, 1/6 of ending at each of 2
or 3, and 1/12 of ending at each of 4 or 6.

SAMPLE INPUT:
2

5 5
333333336 333333336 0 0 0
1 2
2 3
3 4
4 5
1 5

5 5
0 0 0 0 0
1 2
2 3
2 4
1 4
1 5

SAMPLE OUTPUT:

777777784 222222224 0 0 0
0 0 333333336 0 666666672

For the first test case, p1 ≡p2≡1/3(mod 109+7). Bessie has probability 7/9
of ending at 1 (taking one of the paths 1, 1→2→3→4→5→1, or 1→5→4→3→2→1) and 2/9 of ending at 2.

For the second test case, Bessie has probability 1/3 of ending at 3, and 2/3 of ending at 5.

SAMPLE INPUT:

1

11 13
2 3 4 5 6 7 8 9 10 11 12
1 2
1 3
2 3
2 4
4 5
2 5
4 8
5 9
2 6
6 7
2 7
6 10
5 11

SAMPLE OUTPUT:

133332478 200000394 577778352 999999971 399999938 933333282 355555536 800000020 18 600000029 18

SCORING:

Inputs 4-5: N≤11
Inputs 6-7: There are no simple cycles.
Inputs 8-11: No island lies on more than one simple cycle.
Inputs 12-15: No island lies on more than 5 simple cycles.
Inputs 16-19: No island lies on more than 50 simple cycles.
Inputs 20-23: No additional constraints.

Problem credits: Benjamin Qi

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USACO竞赛考多少分能晋级?USACO竞赛晋级通过率是多少?

2024年的第三场月赛即将在2月开始,持续四天。在赛程内,只要连续参赛四小时,就可以参加比赛!如果错过了USACO的第二场月赛,那就别再错过第三场了!该场比赛将给许多同学展示他们的才华和竞争力。

USACO竞赛考多少分能晋级?

USACO竞赛的晋级分数线在不同级别和不同场次会有所不同。

以2022-2023赛季为例,以下是一些晋级分数线的参考范围:

- Bronze级别:晋级分数线大致在700~750之间,有时在题目相对简单的场次,分数线可能会达到800分。

- Silver级别:晋级分数线一般在650~750之间。

- Gold级别:晋级分数线也在650~750之间。

此外,参赛者还应注意控制考试时间,在每个题目上不要花费过多时间。三道题目总共1000分满分,做对两道半题大约可以达到750分,850分左右可以确保通过。

同时注意考试时间,控制在一题60分钟之内,不要在一题上花太多时间。三道题1000分满分,做对两道半题750分一般可以晋级,850分可以确保通过。

USACO竞赛晋级通过率是多少?

Bronze 通过率就在15%左右。

Silver 5%~6%左右

Gold 的通过率大概在 2%~3% 左右。

备赛注意事项

提升算法分析能力:

USACO竞赛学习可以帮助学生提升算法分析能力。在比赛中,学生需要根据题目的条件快速判断所需的算法,并将解题过程整理成步骤。通过不断练习和思考,学生可以培养出快速分析问题和选择合适算法的能力。

增强代码编写能力:

USACO竞赛学习对于提升代码编写能力至关重要。在比赛中,学生需要将思考步骤转化为代码,并通过计算机进行求解。通过参加竞赛并解决一系列编程问题,学生可以不断提升自己的编码能力,包括代码的逻辑性、可读性和效率性。

具备数理逻辑能力:

数理逻辑能力在编程中也是非常重要的技能。USACO竞赛学习可以帮助学生培养数理逻辑能力。优秀的学生能够更好地理解和运用算法运算,并能够通过数学和逻辑推理解决问题。通过解决竞赛中的问题,学生可以锻炼自己的数理逻辑思维能力,提高解决问题的效率和准确性。

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USACO信奥赛第二场月赛复盘!考多少分能拿奖?

USACO信息学奥赛是当下备受欢迎的国际信息学奥赛,全年的活动赛季从每年12月份一直持续到次年3月份。在5月份,国家集训队将从参赛选手中选拔出来。不论是初学编程的新手还是已经实力不凡的高手,只要对编程计算机方向感兴趣,USACO竞赛体系都是值得了解的。

USACO信奥赛第二场月赛是从1月26日开赛的,到1月29日截止。选手可以参加的时间横跨一个4天的时间窗口,在时间窗口内任选连续的约四小时参赛。中途下线参赛计时不会停止,自开始计四小时后会自动结束参赛。

在1月27到28就故障不断,28号彻底无法访问。官方也及时给出了处理回复,到28日上午全面解决,1月29日全天学生都是可以正常在官网答题的。USACO Director、美国国家队总领队Brian Dean博士针对本次事故在官网给出了正面回应:目前已经转移到了新的服务器,并正在研究弥补方案,比如在本赛季末增加一场比赛(未确定)

USACO竞赛晋级规则

USACO 各级别的晋级顺序为“铜→银→金→白金”,需要逐级参赛、逐级晋级。如果选手实力强劲,在某个月的当前级别直接拿到了满分成绩,系统会提示直接在当月晋级下一级别。

而没拿到满分的选手就需要在当月的比赛结束、官方统计划定晋级线后,才能知道自己下个月参赛时是在当前级别还是下一级别。升级后级别将持续保留,跨年度亦不发生改变。

USACO竞赛分数线

从USACO竞赛近几年的晋级分数线来看:USACO竞赛达到750分或800分以上就能晋级。

目前第二场的晋级分数线还没有出来,我们可以先参考12月第一场USACO竞赛的晋级分数线:

青铜级别总参赛人数为12591,晋级分数线为700分+

白银级别总参赛人数为3841,晋级分数线为750分+

黄金级别总参赛人数为1375,晋级分数线为800分+

铂金级别的晋级人数为673

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USACO竞赛各级别考核哪些知识点?冲刺复习阶段应该做什么?

美国USACO信息学奥赛作为计算机科学学生的首选比赛,能够大大增加被藤校及G5名校录取的概率。哈佛、耶鲁、麻省理工、康奈尔、普林斯顿、卡内基梅隆等著名理工牛校都高度认可USACO竞赛奖项。而且,MIT官网明确指出参加这一国际比赛可以提升学术背景实力。

青铜级别

考核知识点:分支和循环,嵌套可变循环,列表、函数、二维列表,基础数组, 多重循环,复合判断、枚举算法

白银级别

考核知识点:基本数据结构、贪心、递归、递推等基本算法

黄金级别

考核知识点:堆、栈、树、链表等高级数据结构,动态规划等高级算法,算法时间和空间复杂度

铂金级别

考核知识点:各类高级的数据结构,尤其是需要算法的时间和空间复杂度,总分1000分。每道题333.3分。

USACO竞赛冲刺复习阶段注意事项:

重温旧题:复习阶段不要只刷新题,而是将以前做错或不会的题目拿出来重新梳理思路,用比赛心态和状态重做一遍。这样可以加深对题目的理解,发现新的解题思路和技巧。

复习常考知识点:根据USACO竞赛的考点,重点复习常考的知识点。例如,银级常考的知识点包括排序、二分查找和并查集;金级常考的知识点包括动态规划、最短路径等算法。查漏补缺,确保对这些知识点有深入的理解和掌握。

形成模板:在复习过程中,可以整理一些常用的算法和数据结构的模板。这样在考试时可以利用模板,节省时间,提高解题效率。同时,模板的整理过程也是对知识点的巩固和回顾。

长期训练和学习:USACO竞赛的难度较高,需要长时间踏实的训练和学习。不仅要掌握基本的编程和算法知识,还需要不断进行实际的练习和应用。青铜到白银的升级需要备考3-6个月,白银到黄金需要备考8-12个月,黄金到铂金需要备考12-24个月。

扫码免费领取USACO知识点思维导图 + 备考书单

USACO竞赛冬季班课开启,提前锁定席位,扫码了解课程详情!