Usaco translation: Three Questions of Usaco (1)

Usaco JAN (Topic i)

I. Overview of the topic

Name of Chinese title	Gift	Delivery route	Game Combination Technology
Name of English title	Gifts	Delivery	Combos
Executable file name	Gifts	Delivery	Combos
Enter file name	Gifts.in	Delivery.in	Combos.in
Output file name	Gifts.out	Delivery.out	Combos.out
Time limit per test point	1 seconds	1 seconds	1 seconds
Number of test points	10	10	10
Score per test point	10	10	10
Comparison mode	Full-text comparison	Full-text comparison	Full-text comparison

Second, running memory limit

Running Memory caps

M

M

M

Note: Thank Lao Hu for his translation. "The error will be there, the statement is not so smooth ..."

1. gift {Bronze 1}

"Problem description"

FJ plans to send gifts to his N (1 <= n <= 1000) cattle with his B (1 <= b <= 1,000,000,000) Yuan budget.

The purchase of the gift of the first cow is spent P (i) yuan, the courier fee is S (i) Yuan. FJ has a coupon that can buy the same gift at half price, if it's always a gift I, then the total cost he spends on this gift is P (i)/2+s (i), coincidentally, p (i) must be an even number.

Please calculate how many cows fj can give gifts.

"File Input"

The first line, two integers, is n and b, respectively.

2nd.. N+1 lines, two integers per line, representing P (i) and S (i), respectively.

(0 <= P (i), S (i) <= 1,000,000,000).

"File Output"

An integer in which FJ can give gifts to as many cows as possible.

"Input Sample"

5 24

4 2

2 0

8 1

6 3

12 5

"Output Example"

4

"Sample description"

Buy 1 to 4 gifts, coupons for 3 use, (4+2) + (2+0) + (4+1) + (6+3) = 22, he can also use coupons at 1 or 4.

2. Fence paint {silver title 1}

"Problem description"

FJ has n (1 <= n <= 100) farms, each with a separate integer coordinate (x_i, y_i). He needed a distribution route, starting from the 1th farm, followed by farm 1, Farm 2, farm 3, and finally from farm N back to farm 1.

FJ can only walk in four directions each time, not walking a unit length of 1 minutes, in addition to farm 1, other farms can and can only be reached once.

Please calculate the minimum time spent on FJ.

"File Input"

The first line, an integer n.

2nd.. N+1 lines, two integers per line x_i and y_i (1 <= x_i, y_i <= 1,000,000).

"File Output"

A row, an integer that represents the minimum time spent. No solution is output-1.

"Input Sample"

4

2 2

2 4

2 1

1 3

"Output Example"

12

"Sample description"

FJ can complete his delivery route within 12 minutes: 2 minutes from the farm to 1 to 2 farms, 5 minutes from farm 2 to 3 farms (bypassing farm 1), 3 minutes to go from Farm 3 to farm 4, 2 minutes from farm 4 back to farm 1.

3. Game combination skill {Gold 1}

"Problem description"

Bessie is playing a game where only three skill keys "A" "B" "C" are available, but these keys can be used to form a specific combination of N (1 <= n<= 20). The first combination technique is represented by a string of length 1 to 15 s_i.

When Bessie entered a sequence of characters and a combination of techniques to match, he would get 1 points. Special, he entered a sequence of characters may be at the same time and a number of combinations of techniques, such as n=3, 3 combinations of "ABA", "CB", and "ABACB", Jobessi input "ABACB", he will get 3 points.

Jobessi input exactly K (1 <= k <= 1,000) characters, how many points can he get?

"File Input"

The first line, two integers n and K.

2nd.. N+1 lines, one string per line, represent a combination of techniques.

"File Output"

A row, an integer that represents the maximum score.

"Input Sample"

3 7

ABA

Cb

Abacb

"Output Example"

4

"Sample description"

Input Abacbcb,aba 1 points, ABACB 1 points, CB 2 points.

Usaco translation: Three Questions of Usaco (1)