C++ :: STL Map Compare Operator
Jun 13, 2012In stl map, if I insert two keys, say a and b. It looks like compare operator is called twice. First time a<b is called and second time b<a is called. Why are both a<b and b<a called?
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C++ :: Namespaces / Classes - Perform Operator Overload With Insertion Operator
Mar 22, 2013I'm doing a refresher for C++ and have gotten to operator overloading. I'm trying to perform an operator overload with the insertion (<<) operator, but I have encountered a problem.
Here's my class [In a header file "Shinigami.h"]
#include<string>
namespace K{
class Quincy;
class Shinigami{
friend std::ostream& operator<<(std::ostream&, const Shinigami&);
[Code] .....
If the operator function is a friend of the 'Shinigami' class, why doesn't it recognize any of it's private members? I need it to be in this file because I'm doing a bit of association with the 'Quincy' class.
I thought it was the namespace, but I included that.
C :: Can't Compare 8 Bit Value With 16 Bit Value
Jun 24, 2014Apart from compiling i am running a software to test for compliance with standards. I always get the following warnings.Implicit binary conversion from one (type) to (type). The type in general can be unsinged int, long etc. There are several cases in which this happens. Like in an if statements, i made sure that both the types are of the same type by type casting.Is it true that i cannot compare an 8 bit value with 16 bit value? I cannot compare a signed value with an unsigned value?what are the exact rules for this?
In an assignment operator i cannot assign a bigger value to the smaller value. Am i correct?Suppose if i multiply a varaible with constant then the constant should be type casted to the same value as the variable?Also if i am shifting a variable say test1 << 1. Then should 1 also need to be typecasted. How to handle situations if the variable is a complex structure or union? i am very much cofused not able to follow definite rules and mostly trying trial and error and i dont want to do that way.
C++ :: Compare Two Strings Of Numbers
Jan 4, 2014I am trying to figure out how to go about comparing two strings of numbers. I have two files that both contain numbers 1-50, one file has multiple repeating numbers while the other one just has 1-50.
I want to compare the files and count how many of each number a occurred and make a chart with * next to the number. First I figured I would use the strings like an array and compare them using nested loops. Then I noticed I have single and double digit numbers. The numbers in the files are printed as:
1 44 5 34 4
2 22 7 55 4
...... etc
Compared too:
1
2
3
4
5
......
50
I thought about using string stream and converting the string to int but wouldn't it just be a huge number when set to the int variable? Then I thought about a array initialized with 1-50 and compared to the file but I still have the issue with single and double digit numbers.
My question is how can I just read one number at a time, either double or single digit?
C++ :: How To Compare Two Double Values
Mar 24, 2014I want to compare two double values
double x = 3072.00000000;
double y = 3072.0000000;
when checking with if its not working
if(x==y) it not working
C++ :: Compare Function On Sets
Oct 18, 2014How can I declare a set of strings that i want to be ordered by a boolean function Comp? Like the one you would write in
sort(v.begin(), v.end(), comp);
I tried
set<string, Comp> S;
but it doesn't work
And the same question for priority queues, can you specify the function you want your elements to be sorted by?
C++ :: How To Compare Similarity Of Two Vectors
Mar 8, 2013This is possibly more of an algorithm question rather than c++ related.Suppose I have two vectors:
std::vector<double> first = {1.0,2.01,3.05,4.05};
std::vector<double> second = {1,2,3,3,4}; // very similar except no decimals and a second "3"
And now I want an algorithm that will tell me how similar these two vectors are. That is, I want to know how much of first is similar to second.
C++ :: Compare Any Two Numbers Input
Jan 11, 2015Program is about to compare any two numbers input. Then, it will display whether the number is minimum or maximum. Use switch statement.
#include <iostream>
using namespace std;
void main() {
int num1, num2;
cout << "Input 2 integers separated by a space. " << endl;
cin >> num1 >> num2;
[Code] .....
C++ :: OOP Compare Member Function
Feb 10, 2015I have an assignment in my OOP c++ class and I had to create a class called date and one of the member functions is a compare function that compares two dates that are taken in. It is suppose to be something like this:
Date d1(12,25,2003);// Dec 25, 2003
Date d2(5,18,2002);// May 18, 2002
d1.Compare(d2);// returns 1 (since d2 comes first)
d2.Compare(d1);// returns -1 (calling object is d2, comes first)
Then if d1 and d2 are equal then it returns 0.
This is what he gave us to start with the function:
int Date::Compare(const Date& d) {
}
C++ :: Compare Value In Switch Statement?
Sep 23, 2013is it possible to compare value in switch statement? i.e: a > b
View 5 Replies View RelatedC++ :: Can't Compare Char Strings
Jun 13, 2013I have two char* that have the same data in (hypothetically).
std::vector<char*> Buff;
Buff = Split(Line, '.');
char* A = "data", B;
B = Buff.at(0)
Where Split is a function that I made to split a string (Line in this case) into a char* vector, this string contains a line from a file. Line is char* too. The weird problem is when Buff data stored in its 0 position is given to B... because B is equal to A (hypothetically) but when this is compared to do certain functions they doesn't match!
Here an example:
std::vector<char*> Buff;
Buff = Split(Line, '.');
char* A = "map", B;
B = Buff.at(0) // Buff.at(0) should be "map" and is apparently "map"
[Code].....
NOTE: I didn't use switch to compare Cmd because I want it separately for easier debugging.
Is there something wrong with my codes?? or what happened here with those hex values before the string in my variables?
C# :: Compare Tree Views?
Aug 7, 2014I have two Tree views populated from XML files. I have them loaded side by side in a windows form. treeView1 and treeView2. I need to compare these two treeviews and highlight any difference in any of the nodes. I am using C#.NET Visual Studio 2012 professional.
treeView1
BIOS_DETAILS
-Manufacturer
-- Hewlett Packard
[Code].....
I need to compare these and highlight the differences in color.
C++ :: How To Compare Two Histograms Using Opencv
Mar 6, 2013I am tying to compare two histograms, but it gives error. Here I have given my code, histogram file and error message. Histogram file 3*5 matrix(output_test.txt):
1 2 3 4 5
5 2 1 4 2
2 1 2 4 2
code:
int main(..........)
{ ................................................
Mat first_histogram(1,feature_vector_size, CV_32F);
Mat second_histogram(1,feature_vector_size, CV_32F);
for(i=0;i<count_row;i++)
{
for(j=0;j<count_row;j++)
{
[Code]...
Error message: error LNK2019: unresolved external symbol "double __cdecl cv::compareHist(class cv::Mat const &,class cv::Mat const &,int)" (?compareHist@cv@@YANABVMat@1@0H@Z)
C# :: Compare Value From Array Against A Word?
Jul 28, 2014I'm trying to put my array value within a conditional against a word, but what can I check that
if(char[1]= "word")
{
AGEW2.Text = string.Format("{0} "whatever" {2}", split);
}
C# :: Compare One Value To A Previously Entered Value?
Oct 3, 2014I am currently taking a C# class. Our current assignment has us entering a player name, and number of hits and displaying these in one set of labels. I have coded everything for the primary function of this program and it works. However, I also have to have a second set of labels that show the highest number of hits entered (if I enter 44, the first and second labels change to 44; if I then enter 27, the first label changes to 27 and the second stays at 44; and if i enter 55, the first label changes to 55 and the second label changes to 55) and the corresponding player name. I have tried searching and reading and I can't seem to figure out how this is done.
View 5 Replies View RelatedC/C++ :: Queries Using String Compare
Oct 31, 2014I am trying to get a list of queries to work right now. I have it so that the user will input 1 of 5 things to compare twin primes in a list. I am just trying to get the queries working fully before actually determining the twin primes that need to be output. The console input will be something like "<= 61" and will display all twin primes from 3 to 61, inclusive.
Well, I thought I had it 100%... Then I realized I have a problem, though. So, I'm reading the string in until a space so I can read in the number after that. So that works fine, but then I also want the "all" and "random" console inputs to work, but they won't unless I put a space after them, which is what I'm trying to avoid...
So, I tried just simply asking for another console input after all of my if statements for the string compare after the first console input. That obviously doesn't work either, though, because it still only wants the first "getline" where it reads until the whitespace.
How to be able to do both on the same console input... The relevant code is posted below:
cout << endl << "What do you want to know about your list of twin primes?" << endl;
string qprompt1;
string qprompt2;
getline(cin, qprompt1, ' ');
string comp1 = ">";
string comp2 = ">=";
[Code] .....
C/C++ :: Can Use Modulo To Compare Two Floats?
Nov 6, 2012Can we use modulo to compare two floats?
View 3 Replies View RelatedC Sharp :: How To Compare Value With Same Textbox In C#
Jan 26, 2015I have a text format like this:
12-22-24-22-33-13
When user click a button then check for duplicated number in that text. How to handle this in C#.
C++ :: Rules To Compare Two Strings Object
Sep 1, 2014In my book I have the following example : Code:
std::string str = "Hello";
std::string phrase = "Hello world";
std::string slang = "Hiya"; and i have these two rules to compare 2 strings object :
if two strings have different lenghts and if every character in the shorter string is equal to the corresponding character of the longer string, than the shorter string is less than the longer string.
if any characters at corresponding positions of two strings differ, then the result of the string comparison is the result of comparing the first character at wich the strings differ then my book says : if we apply the rules of the comparison we know that phrase is greater than str( ok i've understood this ) and that slang is greater than both slang and phrase ( why ?)
explain me rule number two ? in phrase and slang the characters differ and the first character that differ is not H so why my book says slang is bigger than phrase ?
C++ :: Compare Memory Addresses On The Stack?
Dec 4, 2014Jumping into C++, question 5 page 181:
"Write a program that compares the memory addresses of two different variables on the stack and prints out the order of the variables by numerical order of their addresses.
Does my solution look correct
Code:
#include <iostream>
using namespace std;
int main() {
int one = 1;
int two = 2;
if (&one < &two)
cout << one << " " << &one << " " << two << &two << endl;
else
cout << two << " " << &two << " " << one << " " << &one << endl;
}
C++ :: Compare Two Strings To See Which Comes First In Alphabetical Order
Oct 14, 2013How would you compare two strings in an if statement to determine which comes first in alphabetical order?
Try and keep it simple because i am currently new to the language
C :: Assigning String To Array And Compare It?
Mar 20, 2013I have this code :
#include <errno.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
[Code] ...
And this error occued with me I don't know why ???
myHeader.h:42:19: error: expected ")" before string constant
This code is compiled from file called myHeader.h ...
C :: How To Compare 2D Array Rows Separately
Nov 1, 2013I am trying to write a program that prints a 2d array to the screen and then compares each row and column to see if there is any pairs of letters. basically something that looks like this:
---------------------------
V T A Y U C B
D F W Q Q C R
D A L Y M F G
O A S S D T I
Number of horizontal pairs: 2
Number of vertical pairs: 3
---------------------------
so far this is my code below, but i dont know how to approach the comparisons
Code:
#include<stdio.h>
#include<stdlib.h>
#include<time.h>
int main( void )
[code]....
C# :: Default Equality Compare Of Guid?
Apr 27, 2012I have a dictionary which maps a Guid to Orders, it contains like 350000 orders
Code:
Dictionary<Guid, Order> htPreOrders = new Dictionary<Guid, PreOrder>(350000);
Im trying to optimize it by replacing the IEqualityComparer by a custom one.
Code:
class Comp : IEqualityComparer<Guid> {
public bool Equals(Guid x, Guid y) {
return x == y;
}
public int GetHashCode(Guid obj) {
return obj.GetHashCode();
}
Dictionary<Guid, Order> htPreOrders = new Dictionary<Guid, PreOrder>(350000, new Comp()); would this be faster, or is that the same as the default equality compare of Guid?
C :: Does Function Compare Word With Spaces
Sep 7, 2013I was wondering about the function strcmp(), does the function compare word with spaces? eg: If I have two same words "Harith Javed"; will it match both words??
View 8 Replies View RelatedC++ :: Compare Single Value With A Value From Linked Lists
May 2, 2013I'm trying to compare a single value with a value from my Linked list and if they are same, I want to add the value from the list to new list. In other words I want to create a new List with values with the first one. Here is the code that I made, but it's not working.
This is the code with which I search in the first list for a node with a value. In the main() function I have A.find_city(), so it can start from the start_pointer from the first list:
void List::find_city() {
List *temp1;
int b = 0;
char city[20];
cout << "Enter city: ";
cin >> city;
temp1 = start_ptr;
[Code] ....
This is the code with which I add a node to the new list:
void List::in(List *temp1) {
List *temp2;
if(start_ptr == NULL)
start_ptr = temp1;
[Code] ....