对 HTTP 304 的理解

304 的标准解释是：Not Modified 客户端有缓冲的文档并发出了一个条件性的请求（一般是提供If-Modified-Since头表示客户只想比指定日期更新的文档）。服务器告诉客户，原来缓冲的文档还可以继续使用。

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[ACM_HDU_3177]Crixalis's Equipment

Crixalis's Equipment

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 1350 Accepted Submission(s): 543

Description

Crixalis - Sand King used to be a giant scorpion(蝎子) in the deserts of Kalimdor. Though he's a guardian of Lich King now, he keeps the living habit of a scorpion like living underground and digging holes.

Someday Crixalis decides to move to another nice place and build a new house for himself (Actually it's just a new hole). As he collected a lot of equipment, he needs to dig a hole beside his new house to store them. This hole has a volume of V units, and Crixalis has N equipment, each of them needs Ai units of space. When dragging his equipment into the hole, Crixalis finds that he needs more space to ensure everything is placed well. Actually, the ith equipment needs Bi units of space during the moving. More precisely Crixalis can not move equipment into the hole unless there are Bi units of space left. After it moved in, the volume of the hole will decrease by Ai. Crixalis wonders if he can move all his equipment into the new hole and he turns to you for help.

Input

The first line contains an integer T, indicating the number of test cases. Then follows T cases, each one contains N + 1 lines. The first line contains 2 integers: V, volume of a hole and N, number of equipment respectively. The next N lines contain N pairs of integers: Ai and Bi.
0

Output

For each case output "Yes" if Crixalis can move all his equipment into the new hole or else output "No".

2

20 3
10 20
3 10
1 7

10 2
1 10
2 11

Yes
No

HDU3177

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[HDU_ACM_Steps]Chapter One Section One

A+B for Input-Output Practice (I)

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 13098 Accepted Submission(s): 6187

Description

Too easy?! Of course! I specially designed the problem for acm beginners.
You must have found that some problems have the same titles with this one, yes, all these problems were designed for the same aim.

Input

The input will consist of a series of pairs of integers a and b, separated by a space, one pair of integers per line.

Output

For each pair of input integers a and b you should output the sum of a and b in one line, and with one line of output for each line in input.

1 5
10 20

6
30

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[ACM实验八]ACM程序设计基础（6）

实验项目：ACM程序设计基础(6) 实验目的：掌握C++程序设计基础。 实验要求：使用VC++6.0实现实验要求。 实验内容：

1．猜牌游戏问题，请看简单回溯——猜牌游戏（提示：可以参考实验六的最后一题Crashing Balloon）。
2. 给定n个作业的集合Jn，每一个作业Ji都有两项任务分别在2台机器上完成。每个作业必须先由机器1处理，然后再由机器2处理。求所有作业在机器2上完成处理的时间和最少，并输出最佳调度方案。如：

 机器1 机器2 作业1 2 1 作业2 3 1 作业3 2 3

3. 电路布线问题，请看简单动态规划——电路布线

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