comparison between signed and unsigned integer expressions [问题点数:30分,结帖人johnx123]

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char分三类:char,signed,unsigned ?为什么?
Expressions
DescriptionnnArithmetic <em>expressions</em> are usually written with the operators in <em>between</em> the two operands (which is called infix notation). For example, (x+y)*(z-w) is an arithmetic expression in infix notation. However, it is easier to write a program to evaluate an expression if the expression is written in postfix notation (also known as reverse Polish notation). In postfix notation, an operator is written behind its two operands, which may be <em>expressions</em> themselves. For example, x y + z w - * is a postfix notation of the arithmetic expression given above. Note that in this case parentheses are not required.nnTo evaluate an expression written in postfix notation, an algorithm operating on a stack can be used. A stack is a data structure which supports two operations:nnpush: a number is inserted at the top of the stack.npop: the number from the top of the stack is taken out.nDuring the evaluation, we process the expression from left to right. If we encounter a number, we push it onto the stack. If we encounter an operator, we pop the first two numbers from the stack, apply the operator on them, and push the result back onto the stack. More specifically, the following pseudocode shows how to handle the case when we encounter an operator O:nna := pop();nb := pop();npush(b O a);nThe result of the expression will be left as the only number on the stack.nnNow imagine that we use a queue instead of the stack. A queue also has a npush and pop operation, but their meaning is different:nnpush: a number is inserted at the end of the queue.npop: the number from the front of the queue is taken out of the queue.nCan you rewrite the given expression such that the result of the algorithm using the queue is the same as the result of the original expression evaluated using the algorithm with the stack?nnInputnnThe first line of the input contains a number T (T ≤ 200). The following T lines each contain one expression in postfix notation. Arithmetic operators are represented by uppercase letters, numbers are represented by lowercase letters. You may assume that the length of each expression is less than 10000 characters.nnOutputnnFor each given expression, print the expression with the equivalent result when using the algorithm with the queue instead of the stack. To make the solution unique, you are not allowed to assume that the operators are associative or commutative.nnSample Inputnn2nxyPzwIMnabcABdefgCDEFnSample OutputnnwzyxIPMngfCecbDdAaEBF
Comparison of correlation algorithms between GTEM cell and semi anechoic chamber
Comparison of correlation algorithms <em>between</em> GTEM cell and semi anechoic chamber
论文研究-A comparison of exception system between C and Java.pdf
C 与Java异常处理机制的比较,鲍鹏,高珩,本文分别深入讨论了C 与Java的异常处理机制。比较了C 与Java的异常匹配处理,异常类继承体系与异常处理代码的区别,并且讨论了异常�
请问什么是Unsigned Normalized Integer?
我发现跟UINT好像是一样呢?rn有大神出来解释一下吗?
java里面有没有unsigned integer类型?
如果没有这个类型一般用什么可代替这个类型?
关于signed和unsigned、8位、16位、32位整数的比较
你能不通过计算机,给出下面程序的输出结果吗?rnrn#include rnrnconst un<em>signed</em> char cu8 = 0xFF;rnconst un<em>signed</em> short cu16 = 0xFFFF;rnconst un<em>signed</em> long cu32 = 0xFFFFFFFF;rnrnconst <em>signed</em> char cs8 = -1;rnconst <em>signed</em> short cs16 = -1;rnconst <em>signed</em> long cs32 = -1;rnrnvoid main(int argc, char* argv[])rnrn printf("(%u == %d)\t = %d\n", cu8, cs8, cu8 == cs8);rn printf("(%u == %d)\t = %d\n", cu16, cs16, cu16 == cs16);rn printf("(%u == %d)\t = %d\n", cu32, cs32, cu32 == cs32);rnrn printf("(%u == %d)\t = %d\n", cu8, cu16, cu8 == cu16);rn printf("(%d == %d)\t = %d\n", cs8, cs16, cs8 == cs16);rn printf("(%d == %d)\t = %d\n", cs8, cs32, cs32 == cs8);rnrn printf("(%u ^ %d)\t = %d\n", cu8, cs8, (cu8^cs8)==0);rn printf("(%u ^ %d)\t = %d\n", cu32, cs32, (cu32^cs32)==0);rn printf("(%u ^ %d)\t = %d\n", cs32, cu16, (cs32^cu16)==0);rn printf("(%u ^ %d)\t = %d\n", cu32, cs16, (cu32^cs16)==0);rnrnrn问题的关键在于符号位的扩展。rn各位请在运行程序前给答案,让大家辩论一下,以增进对符号扩展的理解,OK?
c语言unsigned int 可以和signed int 比较大小吗
c语言un<em>signed</em> int 可以和<em>signed</em> int 比较大小吗n可以么,为什么~~
vb 的signed数据类型向unsigned数据类型的转化算法
Function UnsingedAdd (ByVal Start As Long, ByVal Incr As Long) As LongrnrnConst SignBit As Long = &H80000000rnUn<em>signed</em>Add=(Start Xor SignBit) + Incr Xor SignBitrnrnEnd Functionrnrn谁能看懂?ByVal Start As Long, ByVal Incr As Long这两个参数是怎么用的,能举个例子说一下么?
C/C++ —— signed 与 unsigned 有符号和无符号数及其移位
un<em>signed</em> int a = 0; un<em>signed</em> int b = -1; // b 为 0xffffffff un<em>signed</em> int c = a - 1; // c 为 0xffffffff
warning C4018: ' : signed/unsigned mismatch这是怎么回事? 请指教
rnint m;rn char c[10];rnrnfor(m=0;m : <em>signed</em>/un<em>signed</em> mismatch这是怎么回事?(字符数组c已赋值)
原码,反码与补码,signed,unsigned char的存储与大小
原码: 如果机器字长为N个bit,那么一个数的原码就是N位二进制数,最高位 是符号位,1代表负数,0代表正数。 反码: 正数的反码就是原码,负数的反码就是符号位不变,其他取反。 补码: 正数的补码与其原码相同;负数的补码是在其反码的末位加1。 (计算机中的数都是以补码形式存储的) 补码的形式是为了进行正负数二进制的加减操作 char为1个字节,8个bit位,看看内存中是怎么存储的
新鸟问题之002:char,signed char,unsigned char
#include rnint main()rn rn int d;rn std::cin>>d;rn rn char a=d;rn <em>signed</em> char b=d;rn un<em>signed</em> char c=d;rnrn std::cout<<
关于C语言数据基本类型的Signed和Unsigned的理解
关于C语言数据基本类型的Signed和Un<em>signed</em>的理解 今天学习C语言的数据这一章遇到了<em>signed</em>和un<em>signed</em> <em>signed</em>表示有符号的,其第一个位表示正负,其余位表示大小,例如<em>signed</em> int 大小区间为-128~127。 un<em>signed</em>表示无符号的,所有位都为大小,没有正负,例如un<em>signed</em> int 大小区间为0~127。 一般未做说明以<em>signed</em>为默认值。 以上为s...
Clang-Tidy use of a signed integer operand with a binary bitwise operator
[img=https://img-bbs.csdn.net/upload/201805/08/1525767694_680199.jpg][/img]rnrn我在CLion上用C实现了一个顺序表,在扩容的时候,我选择扩容为原来的1.5倍,如图代码所示,我用位移操作的时候编译器会报一个警告,这警告百度不到,谷歌出来的更是看不懂。。还请大神们点拨下谢谢!
C++ 有没有什么方法禁止unsignedsigned的混合运算??
比如这段代码rnint a=5;rnDWORD b=4;rnLONGLONG abc= -a + b;rnrnabc的结果可不是-1 ,而是0xffffffff 。rn程序中隐藏这样的错误太可怕了,我的程序里发现了好几处由于sizeof导致的这种问题,因为sizeof返回的是size_t ,实际就是un<em>signed</em> int 。rnrnC++有没有什么方法禁止<em>signed</em>隐式地转化为un<em>signed</em>,或者产生warning也行。rn谢谢。
一个C语言中unsignedsigned的汇编不同的插曲
unsinged 和<em>signed</em>数据类型的不同编译方向。
请问vc里的char默认是signed还是unsigned
请问vc里的char默认是<em>signed</em>还是un<em>signed</em>
char,unsigned char和signed char三种数据类型的区别
char与int,short,long有所不同,ISO C++标准并没有规定它在默认(不加修饰)情况下是有符号的还是无符号的。它会因编译器的 不同而不同。因此,char,un<em>signed</em> char和<em>signed</em> char是三种不同的数据类型。
Whether plain chars are signed or unsigned is machine-dependent , but printable characters are always positive
Whether plain chars are <em>signed</em> or un<em>signed</em> is machine-dependent , but printable characters are always positivern出自 the c programming language 2.2倒數第四段話結尾,覺得這句話中“可以打印的字符總是正的”是不是有點問題啊rn請高人多多指教rn
c语言unsigned int可以和signed int比较大小吗
可以么,为什么[img=https://forum.csdn.net/PointForum/ui/scripts/csdn/Plugin/003/onion/3.gif][/img]
warning C4018: ' : signed/unsigned mismatch 到底出了什么错
LPBYTE CShitDlg::pchar_To_LPBYTE( char * str)rnrn LPBYTE lpb=new BYTE[strlen(str)+1];rn for(int i=0; i < strlen(str);i++)rn lpb[i]=str[i];rn lpb[strlen(str)]=0;rn return lpb;rnrnrnwarning C4018: ' : <em>signed</em>/un<em>signed</em> mismatch 到底出了什么错rnrn这是vc知识库里程序
Hex Comparison
Hex Comparison 是一款二进制文件比较与十六进制编辑工具。它可以帮助你使用二进制格式来比较两个文件。主要功能: 1.允许快速比较两个文件。 2.快速查找每一处不匹配的数据。 3.使用自定义颜色来显示不匹配数据。 4.允许将比较结果保存到文件中。 5.支持快速转换文件的偏移地址。 6.允许创建新的二进制文件。 7.支持通过双击鼠标来查找同步位置。 8.支持滚动没一处不匹配。 9.支持修改二进制文件与文本文件。 10.支持在文件中以二进制或 ASCII 方式进行查找。
between和>
当记录超过上万条记录,是应用于<em>between</em>快呢,还是应用>=和=100 and 字段<=400rnrn 哪个更快些?
standard comparison
communication technoloy standard <em>comparison</em> and analysis
C# comparison
自己总结的C#入门用的ppt,内容比较简单,仅供参考
Brocade-Cisco Comparison
For instance, both Brocade and Cisco layer 3 switches support the Virtual Router Redundancy Protocol (VRRP) as defined in RFC 2338. Proprietary Protocols - In addition to VRRP, Brocade also supports and extended version of VRRP, called VRRPE. VRRPE functions in a similar way to VRRP, but overcomes many of the limitations of the standards-based protocol. Cisco also provides alternatives to the standard-based protocol; Hot Standby Router Protocol (HSRP) and Gateway Load Balancing Protocol (GLBP).
between
select * from spml where spdm <em>between</em> '0002%' and '0004%'rn为什么只查找出0002xxx到0003xxx的?rn同理rnselect * from spml where spdm <em>between</em> '0002%' and '0005%'rn为什么只查找出0002xxx到0005xxx的?
signed char
有人说,char型变量最好限定是<em>signed</em>还是un<em>signed</em>。小妹不明白为什么不能缺省。
Theory Comparison
Problematic Integration, Uncertrianty Management, and Other Curious Constructs_James J
Roman Expressions
Problem DescriptionnAs any other marketing company, ACM produces a lot of funky advertising items that may contain a logo and be given to customers and business partners as small gifts. A unique specialty of ACM is a calculator that uses roman numbers.nnRoman numbers are able to express any non-negative <em>integer</em> using uppercase letters:nnNumbers are created by appending several letters together, the letter representing a higher value must always precede letters with lower values. The only exception are the letters “I”, “X”, and “C”, they may be used before higher letters to form values expressed by digits 4 and 9. The only possible combinations are:nnAny roman number must first express thousands, then hundreds, tens, and ones. Therefore, 499 must always be written as “CDXCIX”, not “ID”.nnAlthough not very practical, this gift is considered extremely “cooooool”. Your task is to write software for that calculator.n nnInputnThe input will consist from commands, each written on a separate line. Possible commands arenassignments, “RESET”, and “QUIT”.nAn assignment command starts with a single digit representing one of ten registers that thencalculator has. The register number is followed by an equal sign (“=”) and an expression. Thenexpression will consist only from valid roman numbers, register names (digits), plus (“+”) andnminus (“-”) signs. You may assume that the expression will always be valid and no longer thann10000 characters.n nnOutputnFor each command, output a single line. For assignments, print the register name, equal sign,nand the value that is being as<em>signed</em> to that register. Instead of it, print the word “Error”, if thenexpression contains a reference to a register that has not been as<em>signed</em> before, or if the resultnis negative or larger than 10000. In such cases, no change to register values is made.nFor RESET commands, invalidate all previous register assignments and print the word “Ready”.nThe QUIT command will be the last one. Print the word “Bye” and terminate the program.n nnSample Inputn1=MC+IV-Xn1=1+1nRESETn1=1+Xn1=MMn1=1+1+1+1+1n2=1+1nQUITn nnSample Outputn1=MXCIVn1=MMCLXXXVIIInReadynErrorn1=MMn1=MMMMMMMMMMnErrornByen
unsigned long跟unsigned int都是32字节,有什么区别。 unsigned char 跟 signed char在表达上有什么区别。
un<em>signed</em> long跟un<em>signed</em> int都是32字节,有什么区别。 rnrnun<em>signed</em> char 跟 <em>signed</em> char在表达上有什么区别。rnrn我知道un<em>signed</em> char是无符号char,高一位不能来表达负数。rnrn我要问的是rnrn在一些通信协议的头文件中,表示多个字符的时候,用无符号char,还是有符号char.rn比如md5编码之后的16字节,用un<em>signed</em> char 还是<em>signed</em> char,为什么。rn存储传输用户名的时候,用un<em>signed</em> char 还是<em>signed</em> char,为什么。rnrn
between 与 not between的问题
请高手看看我下面两个语句:rn语句1rnselect distinct a.str_deductbill_nornfrom [sellrebate].dbo.t_deduct_account_detail arn rnwhere a.str_bill_no <em>between</em> '200812260000' and '200903259999'rnrn and str_deductbill_no='200901070089'rnorder by str_deductbill_norn////rn语句2rnselect distinct a.str_deductbill_nornfrom [sellrebate].dbo.t_deduct_account_detail arn rnwhere a.str_bill_no [color=#FF0000]not[/color] <em>between</em> '200812260000' and '200903259999'rnrn and str_deductbill_no='200901070089'rnorder by str_deductbill_norn以上两个语句的区别是在<em>between</em>前一个有not一个没notrn在本人看来一个两个语句查出的结果是相对的,可是恰恰相反。请问各位这是什么原因?rnrn
between and
select * from a rnwhere a1 <em>between</em> (select b1 from b where to_char(a_date, 'yyyymm') like '%200901%')rnand (select b2 from b where to_char(a_date, 'yyyymm') like '%200901%' )这样写可以吗?谢谢!
在线求解 case expressions must be constant expressions
R.java下面 关键字final不见了rn正确写法rnpublic static final int push_down_on=0x7f040004;rnrn变成现在的样子,rnpublic static int push_down_on=0x7f040004;rn求恢复。
Complicated Expressions
DescriptionnnThe most important activity of ACM is the GSM network. As the mobile phone operator, ACM must build its own transmitting stations. It is very important to compute the exact behaviour of electro-magnetic waves. Unfortunately, prediction of electro-magnetic fields is a very complex task and the formulas describing them are very long and hard-to-read. For example, below are the Maxwell's Equations describing the basic laws of electrical engineering. n![](http://poj.org/images/1400_1.jpg)nnACM has de<em>signed</em> its own computer system that can make some field computations and produce results in the form of mathematic <em>expressions</em>. Unfortunately, by generating the expression in several steps, there are always some unneeded parentheses inside the expression. Your task is to take these partial results and make them "nice" by removing all unnecessary parentheses. nnInputnnThere is a single positive <em>integer</em> T on the first line of input. It stands for the number of <em>expressions</em> to follow. Each expression consists of a single line containing only lowercase letters, operators (+, -, *, /) and parentheses (( and )). The letters are variables that can have any value, operators and parentheses have their usual meaning. Multiplication and division have higher priority then subtraction and addition. All operations with the same priority are computed from left to right (operators are left-associative). There are no spaces inside the <em>expressions</em>. No input line contains more than 250 characters.nOutputnnPrint a single line for every expression. The line must contain the same expression with unneeded parentheses removed. You must remove as many parentheses as possible without changing the semantics of the expression. The semantics of the expression is considered the same if and only if any of the following conditions hold: nnThe ordering of operations remains the same. That means "(a+b)+c" is the same as "a+b+c", and "a+(b/c)" is the same as "a+b/c". nThe order of some operations is swapped but the result remains unchanged with respect to the addition and multiplication associativity. That means "a+(b+c)" and "(a+b)+c" are the same. We can also combine addition with subtraction and multiplication with division, if the subtraction or division is the second operation. For example, "a+(b-c)" is the same as "a+b-c". nnYou cannot use any other laws, namely you cannot swap left and right operands and you cannot replace "a-(b-c)" with "a-b+c". nnSample Inputnn8n(a+(b*c))n((a+b)*c)n(a*(b*c))n(a*(b/c)*d)n((a/(b/c))/d)n((x))n(a+b)-(c-d)-(e/f)n(a+b)+(c-d)-(e+f)nSample Outputnna+b*cn(a+b)*cna*b*cna*b/c*dna/(b/c)/dnxna+b-(c-d)-e/fna+b+c-d-(e+f)
Expressions 白皮书
数据库SQL_SERVER2005 详细表达式用法介绍
sumount -signed
可以su卸载的操作,在twp中刷入,并且可以除原有的supersu的权限
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