-
RSA算法 :首先, 找出三個(gè)數(shù), p, q, r, 其中 p, q 是兩個(gè)相異的質(zhì)數(shù), r 是與 (p-1)(q-1) 互質(zhì)的數(shù)...... p, q, r 這三個(gè)數(shù)便是 person_key，接著, 找出 m, 使得 r^m == 1 mod (p-1)(q-1)..... 這個(gè) m 一定存在, 因?yàn)?r 與 (p-1)(q-1) 互質(zhì), 用輾轉(zhuǎn)相除法就可以得到了..... 再來(lái), 計(jì)算 n = pq....... m, n 這兩個(gè)數(shù)便是 public_key ，編碼過(guò)程是, 若資料為 a, 將其看成是一個(gè)大整數(shù), 假設(shè) a < n.... 如果 a >= n 的話(huà), 就將 a 表成 s 進(jìn)位 (s
標(biāo)簽：
person_key
RSA
算法
上傳時(shí)間：
2013-12-14
上傳用戶(hù)：zhuyibin
-
數(shù)字運(yùn)算，判斷一個(gè)數(shù)是否接近素?cái)?shù)
A Niven number is a number such that the sum of its digits divides itself. For example, 111 is a Niven number because the sum of its digits is 3, which divides 111. We can also specify a number in another base b, and a number in base b is a Niven number if the sum of its digits divides its value.
Given b (2 <= b <= 10) and a number in base b, determine whether it is a Niven number or not.
Input
Each line of input contains the base b, followed by a string of digits representing a positive integer in that base. There are no leading zeroes. The input is terminated by a line consisting of 0 alone.
Output
For each case, print "yes" on a line if the given number is a Niven number, and "no" otherwise.
Sample Input
10 111
2 110
10 123
6 1000
8 2314
0
Sample Output
yes
yes
no
yes
no
標(biāo)簽：
數(shù)字
運(yùn)算
上傳時(shí)間：
2015-05-21
上傳用戶(hù)：daguda
-
源代碼\用動(dòng)態(tài)規(guī)劃算法計(jì)算序列關(guān)系個(gè)數(shù)
用關(guān)系"<"和"="將3個(gè)數(shù)a，b，c依次序排列時(shí)，有13種不同的序列關(guān)系：
a=b=c,a=b<c,a<b=v,a<b<c,a<c<b
a=c<b,b<a=c,b<a<c,b<c<a,b=c<a
c<a=b,c<a<b,c<b<a
若要將n個(gè)數(shù)依序列，設(shè)計(jì)一個(gè)動(dòng)態(tài)規(guī)劃算法，計(jì)算出有多少種不同的序列關(guān)系，
要求算法只占用O(n),只耗時(shí)O(n*n).
標(biāo)簽：
lt
源代碼
動(dòng)態(tài)規(guī)劃
序列
上傳時(shí)間：
2013-12-26
上傳用戶(hù)：siguazgb
-
The government of a small but important country has decided that the alphabet needs to be streamlined and reordered. Uppercase letters will be eliminated. They will issue a royal decree in the form of a String of B and A characters. The first character in the decree specifies whether a must come ( B )Before b in the new alphabet or ( A )After b . The second character determines the relative placement of b and c , etc. So, for example, "BAA" means that a must come Before b , b must come After c , and c must come After d .
Any letters beyond these requirements are to be excluded, so if the decree specifies k comparisons then the new alphabet will contain the first k+1 lowercase letters of the current alphabet.
Create a class Alphabet that contains the method choices that takes the decree as input and returns the number of possible new alphabets that conform to the decree. If more than 1,000,000,000 are possible, return -1.
Definition
標(biāo)簽：
government
streamline
important
alphabet
上傳時(shí)間：
2015-06-09
上傳用戶(hù)：weixiao99
-
電力系統(tǒng)在臺(tái)穩(wěn)定計(jì)算式電力系統(tǒng)不正常運(yùn)行方式的一種計(jì)算。它的任務(wù)是已知電力系統(tǒng)某一正常運(yùn)行狀態(tài)和受到某種擾動(dòng)，計(jì)算電力系統(tǒng)所有發(fā)電機(jī)能否同步運(yùn)行
1運(yùn)行說(shuō)明：
請(qǐng)輸入初始功率S0，形如a+bi
請(qǐng)輸入無(wú)限大系統(tǒng)母線(xiàn)電壓V0
請(qǐng)輸入系統(tǒng)等值電抗矩陣B
矩陣B有以下元素組成的行矩陣
1正常運(yùn)行時(shí)的系統(tǒng)直軸等值電抗Xd
2故障運(yùn)行時(shí)的系統(tǒng)直軸等值電抗X d
3故障切除后的系統(tǒng)直軸等值電抗
請(qǐng)輸入慣性時(shí)間常數(shù)Tj
請(qǐng)輸入時(shí)段數(shù)N
請(qǐng)輸入哪個(gè)時(shí)段發(fā)生故障Ni
請(qǐng)輸入每時(shí)段間隔的時(shí)間dt
標(biāo)簽：
電力系統(tǒng)
正
計(jì)算
運(yùn)行
上傳時(shí)間：
2015-06-13
上傳用戶(hù)：it男一枚
-
上下文無(wú)關(guān)文法（Context-Free Grammar, CFG）是一個(gè)4元組G=(V, T, S, P)，其中，V和T是不相交的有限集，S∈V，P是一組有限的產(chǎn)生式規(guī)則集，形如A→α，其中A∈V，且α∈(V∪T)*。V的元素稱(chēng)為非終結(jié)符，T的元素稱(chēng)為終結(jié)符，S是一個(gè)特殊的非終結(jié)符，稱(chēng)為文法開(kāi)始符。
設(shè)G=(V, T, S, P)是一個(gè)CFG，則G產(chǎn)生的語(yǔ)言是所有可由G產(chǎn)生的字符串組成的集合，即L(G)={x∈T* | Sx}。一個(gè)語(yǔ)言L是上下文無(wú)關(guān)語(yǔ)言（Context-Free Language, CFL），當(dāng)且僅當(dāng)存在一個(gè)CFG G，使得L=L(G)。 *⇒
例如，設(shè)文法G：S→AB
A→aA|a
B→bB|b
則L(G)={a^nb^m | n,m>=1}
其中非終結(jié)符都是大寫(xiě)字母，開(kāi)始符都是S，終結(jié)符都是小寫(xiě)字母。
標(biāo)簽：
Context-Free
Grammar
CFG
上傳時(shí)間：
2013-12-10
上傳用戶(hù)：gaojiao1999
-
一:需求分析
1. 問(wèn)題描述
魔王總是使用自己的一種非常精練而抽象的語(yǔ)言講話(huà),沒(méi)人能聽(tīng)懂,但他的語(yǔ)言是可逐步解釋成人能聽(tīng)懂的語(yǔ)言,因?yàn)樗恼Z(yǔ)言是由以下兩種形式的規(guī)則由人的語(yǔ)言逐步抽象上去的:
-----------------------------------------------------------
(1) a---> (B1)(B2)....(Bm)
(2)[(op1)(p2)...(pn)]---->[o(pn)][o(p(n-1))].....[o(p1)o]
-----------------------------------------------------------
在這兩種形式中,從左到右均表示解釋.試寫(xiě)一個(gè)魔王語(yǔ)言的解釋系統(tǒng),把
他的話(huà)解釋成人能聽(tīng)得懂的話(huà).
2. 基本要求:
用下述兩條具體規(guī)則和上述規(guī)則形式(2)實(shí)現(xiàn).設(shè)大寫(xiě)字母表示魔王語(yǔ)言的詞匯 小寫(xiě)字母表示人的語(yǔ)言的詞匯 希臘字母表示可以用大寫(xiě)字母或小寫(xiě)字母代換的變量.魔王語(yǔ)言可含人的詞匯.
(1) B --> tAdA
(2) A --> sae
3. 測(cè)試數(shù)據(jù):
B(ehnxgz)B 解釋成 tsaedsaeezegexenehetsaedsae若將小寫(xiě)字母與漢字建立下表所示的對(duì)應(yīng)關(guān)系,則魔王說(shuō)的話(huà)是:"天上一只鵝地上一只鵝鵝追鵝趕鵝下鵝蛋鵝恨鵝天上一只鵝地上一只鵝".
| t | d | s | a | e | z | g | x | n | h |
| 天 | 地 | 上 | 一只| 鵝 | 追 | 趕 | 下 | 蛋 | 恨 |
標(biāo)簽：
語(yǔ)言
抽象
分
上傳時(shí)間：
2014-12-02
上傳用戶(hù)：jkhjkh1982
-
說(shuō)明
除了自身之外，無(wú)法被其它整數(shù)整除的數(shù)稱(chēng)之為質(zhì)數(shù)，要求質(zhì)數(shù)很簡(jiǎn)單，但如何快速的求出質(zhì)數(shù)則一直是程式設(shè)計(jì)人員與數(shù)學(xué)家努力的課題，在這邊介紹一個(gè)著名的 Eratosthenes求質(zhì)數(shù)方法
解。
以背包問(wèn)題為例，我們使用兩個(gè)陣列value與item，value表示目前的最佳解所得之總價(jià)，item表示最後一個(gè)放至背包的水果，假設(shè)有負(fù)重量 1～8的背包8個(gè)，並對(duì)每個(gè)背包求其最佳解。
標(biāo)簽：
上傳時(shí)間：
2013-12-22
上傳用戶(hù)：二驅(qū)蚊器
-
We have a group of N items (represented by integers from 1 to N), and we know that there is some total order defined for these items. You may assume that no two elements will be equal (for all a, b: a<b or b<a). However, it is expensive to compare two items. Your task is to make a number of comparisons, and then output the sorted order. The cost of determining if a < b is given by the bth integer of element a of costs (space delimited), which is the same as the ath integer of element b. Naturally, you will be judged on the total cost of the comparisons you make before outputting the sorted order. If your order is incorrect, you will receive a 0. Otherwise, your score will be opt/cost, where opt is the best cost anyone has achieved and cost is the total cost of the comparisons you make (so your score for a test case will be between 0 and 1). Your score for the problem will simply be the sum of your scores for the individual test cases.
標(biāo)簽：
represented
integers
group
items
上傳時(shí)間：
2016-01-17
上傳用戶(hù)：jeffery
-
The XML Toolbox converts MATLAB data types (such as double, char, struct, complex, sparse, logical) of any level of nesting to XML format and vice versa.
For example,
>> project.name = MyProject
>> project.id = 1234
>> project.param.a = 3.1415
>> project.param.b = 42
becomes with str=xml_format(project, off )
"<project>
<name>MyProject</name>
<id>1234</id>
<param>
<a>3.1415</a>
<b>42</b>
</param>
</project>"
On the other hand, if an XML string XStr is given, this can be converted easily to a MATLAB data type or structure V with the command V=xml_parse(XStr).
標(biāo)簽：
converts
Toolbox
complex
logical
上傳時(shí)間：
2016-02-12
上傳用戶(hù)：a673761058
