C++ :: Variable That Can Hold String And Int In Same Time?
Feb 12, 2014Is there a variable that can hold string and int in the same time?
If not, what can I do if I want to input data with string and int like a password for an example.
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C++ :: Hold Group Of Variables In One Variable
Oct 4, 2014So far i know that the pointer is address value to the real variable. Pointer size depends on operation system right?
for example
32bit systems: 4byte pointers
64bit systems: 8byte pointers
128bit systems: 16byte pointers?
Anyways, there have to be an variable type in c++ what can hold a pointer.
Let's imagine that the int is the thing im looking for
struct stc1 {
char *chars;
int ints;
}
struct stc2 {
char *chars;
float floats;
[Code]....
My wish is to hold different types of variable or groups of different type of variables in one variable.
I am developing program in windows now yet it will be used in linux and who knows with what x bit systems.
C++ :: Declaration Of Variable To Hold A Table Of 5 Records
Aug 27, 2014im doing a program to store name, age, time and fitness. and i need to hold a table of 5 such records.can i do this?
#include <iostream>
using namespace std;
int name1, age1, time1, fitness1;
int name2, age2, time2, fitness2;
int name3, age3, time3, fitness3;
int name4, age4, time4, fitness4;
int name5, age5, time5, fitness5;
[code].....
C :: Dividing Time Variable - Always Prints 0
Mar 2, 2013So i have this -
time_t t4 = time(NULL);
//and then some stuff
time_t t5 = time(NULL);
iElapsedYah = t5-t4;
fElapsedYah2 = iElapsedYah/iNumTimes;
printf("It took %f seconds", fElapsedYah2);
but it always prints 0.0000000, and i dont know why even though individually
iElapsedYah = not zero and iNumTimes = not zero
I am using windows 7 and m complier is Dev C++
C++ :: Static Variable To Time Struct
Jan 21, 2013In a function, I have a static variable that I want to assign the time in seconds when a certain condition is met and keep that value until a different condition is met. The time value is a struct. Since now->sec is always incrementing, will timeWhenEventMadeActive below hold onto the initial value or will it increment every time the function is called? I cant seem to test this.
static time_t timeWhenEventMadeActive = 0;
static bool initTime = 0;
if (!initTime) {
timeWhenEventMadeActive = now->sec; //holds uptime value in seconds
[Code] .....
C++ :: Write A Loop Assigning Variable X To All Positions Of String Variable
Sep 8, 2013I have to write a loop assigning a variable x to all positions of a string variable and I'm stuck. I don't have extensive experience with arrays and I'm also a bit confused about C-String. The problem is below.
"Given the following declaration and initialization of the string variable, write a loop to assign 'X' to all positions of this string variable, keeping the length the same.
char our_string[15] = "Hi there!";
(Please note this is a 'C-string', not C++ standard string.)"
C :: Display Current Time And Date In Program And Use Variable To Store Each Of Values
Feb 16, 2013i need to display the current time and date in my program and use variable to store each of the time values like
a = 10
b = 29
c = 31
printf(``%d : %d : %d``, a,b,c);
which then give the output as - 10:29:31
How to save the time in variables in C....
i am using C in windows 7 and my complier is Bloodshed Dev C++
C++ :: Using String And Atoi At Same Time
Aug 25, 2013How do I use string and atoi at the same time?
string scroes;
char input[SIZE];
cout<<" Enter your score" << endl;
cin.getline (input, SIZE);
scores = atoi (input);
C++ :: Date And Time As A String?
Aug 28, 2014This is what I have:
#include <ctime>
#include <string>
using namespace std;
void date_and_time(string &date, string &time){
time_t current_time;
[Code] ......
Is there a way to make sure that the strings would not contain trailing spaces?
C++ :: Converting Time String To Float?
Jun 5, 2013I have a vector<string> of times that I want to convert to vector<double>. The time string is in the form 00:00.000. Is there a STL or something like it algorithm or function to do this, otherwise what would be the best way to do this with a function.
View 3 Replies View RelatedC++ :: Reading String 2 Characters At A Time?
May 10, 2013may i know how do i read a string 2 characters at a time?
lets say i have a for loop like this
for(int i=0;i<stringLen;i++)
{
for(int j=0;j<???;j++)
{
//insert code
}
}
what i want to do is i want to read a string 2 characters at a time and store them into a vector.
C :: Possible To Create Char String At Compile Time?
Mar 28, 2014I would like to have a program with a 5 mb string embedded in it kind of like this:
Code:
const char *c;
c = (const char*)"BEGIN_STRING_HERE, (5 MB of arbitrary values here)";
Is it possible to generate this string at compile time? Maybe with a macro? I'm trying to avoid a source file with a 5 mb string in it.
C/C++ :: Change Enum Type Variable To String Type Variable?
Aug 10, 2014How to change an enum type variable to a string type variable?
View 2 Replies View RelatedC++ :: SDL - Check For A Key That Is Hold Down?
Sep 13, 2013I'm using SDL to try to create a Run and Shoot game. But I do not know how to check if a key is down while the user is HOLDING it.
I do know how to check if a key was pressed.
I have tried with the "event.key.keysym.sym" and "Uint8 *keystate = GetKeyState(NULL)" both worked to check if a key was down but I thought that the GetKeyState(); Function would even check when a key where HELD down
I want my player to move while holding down left or right arrow. So I did something like:
Code:
Uint8 *keystate = GetKeyState(NULL);
if (keystate[SDLK_RIGHT]) {
apply_surface(x++, y, player, screen);
}
How to check if a key is held down?
C :: Reading Three Digits At A Time As One Number In Long String Of Numbers
Nov 29, 2013How can I read a file that contains numbers only, but read it by three digits at a time? I have a long string of numbers and every three digits corresponds to a particular number in itself. i.e. a string of 064045154 would need to be read as '064' '045' and '154'. I need to then subtract one from each of these numbers and the new values I need to convert into their ASCII characters and place these in a new file. This is what I have (focusing on the 'Decrypt' function) but all it does is in the new file place a string of the same character repeated over and over a total number of times equal to the number of integers in the numbers file.
Code:
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "limits.h"
int Encrypt(char * FILENAME)
[Code]..
C++ :: Hold Screen Via GUI To Console
May 15, 2013I had a program (on console) that uses a third-part software to draw some graphs. In order to hold the graphs on the screen, I used cin.get(); and that worked.
Now I created a GUI with Qt. The code remains generally the same. The code continues to call the software to draw graphs (during drawing graphs, there is a console opened automatically). Butcin.get(); in the code cannot hold the graphs on screen anymore. The graphs appear and disappear immediately.
C++ :: Simple Way To Hold Numbers With Lot Of Decimals
Apr 8, 2013I have a task to hold a number like 4.0000000000000000199e+30 and, in a variable like long double (the largest of the data type) doesn't hold the whole number, holds only 4.099e+30, like that.
Any way to hold the whole number?
C/C++ :: How To Use The List Container To Hold A Class
Dec 11, 2013How would I use the list container to hold a class?
class A {
private : int x;
public : void setX(int val) { x = val; }
};
class B {
private : std::list<A> pdata;
public : void addToList();
};
For adding, I thought of trying something like
void B::addToList() {
A *tmp = new A;
if(A != 0) {
tmp->setX(5);
pdata.insert(tmp);
delete tmp;
}
}
How would I do what I'm trying to do? Or is this the wrong way to go about it? For the actual program, "B" would contain several lists of various classes.
C++ :: How To Hold Pointers / References To Abstract Class
Nov 15, 2014I have an abstract class named Terrain, and a class named RoadMap, which supposed to hold an N*N array of Terrains. But I'm not sure what type should the RoadMap class hold:
Code:
#ifndef TERRAIN_H
#define TERRAIN_H
class Terrain {
[Code] ....
I can't use an array of refernces here, so I tried this:
Code: Terrain** terrain; and then I thought this was the way to go:
Code: Terrain (*terrain)[]; But now I'm not sure.
The N*N matrix size supposed to be determined according to a given input... What type should I use there?
C++ :: Create Structure To Hold Data For A Kennel
Apr 3, 2013// This program creates a structure to hold data for a kennel
#include<iostream.h>
struct KennelList {
int dogID;
char gender;
int age;
[Code] ....
C++ :: Template To Hold Two Dimensional Arrays - Automatic Indexing
Mar 6, 2015For the past couple of weeks I have been working on a template to hold two-dimensional arrays. Right now I am puzzling over an indexing question.
There are many places in the template where I would like to use initializer_lists to refer to user-specified row and column ranges, particularly in member function arguments. A typical example would be a member function whose declaration would be along the lines of:
Code:
Array<Type>::some_function(std::initializer_list<int> columns, std::initializer_list<int> rows); which could get called via
Code:
arrayInstance.some_function({3:4}, {5:8});
It would be really nice to be able to use Matlab-style indexing to specify the last column, or the last row, in the Array object -- along the lines of
Code:
arrayInstance.some_function({3:4}, {5:END}); where END takes the value -1, and can be defined in Array, or somewhere else.
The way I have tackled this so far was to write myself an Indices PODS class with two elements to hold start and finish values, and a constructor-from-initializer_list that looks something like this:
Code:
Indices::Indices(std::initializer_list<int> range, int replace_value) {
int const *it = range.begin();
start = (*it == END) ? replace_value : *it ; ++it;
finish = (*it == END) ? replace_value : *it ;
...
}
So the elements of "range" give the values of Indices::start and Indices::finish -- but if either of them are entered as END by the user, they will be replaced by replace_value. (The default value of replace_value is END, so Indices::start and Indices::finish will never change if it is omitted.)
I also defined an Indices::endset(int) function to do the same thing for existing Indices objects:
Code:
Indices::endset(int replace_value) {
if (start == END) start = replace_value;
if (finish == END) finish = replace_value;
} Using Indices::endset, you can code up Array::some_function by modifying the above signature to something like
Code:
Array<Type>::some_function(Indices columns, Indices rows) {
columns.endset(this->M);
rows.endset(this->N);
...
}
This does work, and I've been able to use it in practice. However, it is klutzy. What I would really like to be able to do is have the Indices constructor handle value-replacements in "columns" and "rows", instead of needing to put calls to Indices::endset in every single Array<Type> member function that uses this approach.
The basic problem is that, when Array<Type>::some_function is called, there is no easy way of inserting Array<Type>::M and Array<Type>::N into the optional argument of the Indices constructor when "columns" and "rows" are being built.
The Indices class needs somehow to get access to these, and know which one is being used, M or N. So it needs to have some sort of deeper connection to Array<Type>, but I don't know what that connection should be.
C :: Dynamically Create A New Memo Structure To Hold Memorized Fib
Jun 14, 2013I need to dynamically create a new Memo structure to hold memorized fib #'s.I have two structures:
Code:
typedef struct HugeInteger
{
//array to hold the digits of a huge integer
int *digits;
//number of digits in the huge integer
int length;
}
[code]....
am having trouble with initializing the struct inside of the new Memo, I need the digit fields to null and the length field to 0 to indicate that F[i] has not yet been memoized...I have F->digits and F->length in the for loop but this just simply doesn't work..
C :: Finding Positive / Negative Integers Unsigned Can Hold
Jan 25, 2013Consider a new data type, the mikesint, which can hold 9 bits.
(a) What is the largest integer that an unsigned mikesint can hold?
(b) What is the largest positive integer that a signed mikesint can hold?
(c) What is the largest negative integer that a signed mikesint can hold?
Not sure how to determine this. I'm stuck.
C++ :: Hold Vector Of Pointers In Same Class As Instances Of Those Objects?
Feb 10, 2015Using SFML, I had a Board class which held multiple vectors of all of my object types in the game, and then it also held a vector of pointers to the memory addresses of these object instances, like this
class Board{
//...
std::vector<AbstractObject*> GetAllLevelObjects(){ return allLevelObjects; }
//so these are used to hold my object instances for each level
[Code]....
When looping through this vector and drawing the sprites of the objects, I get the runtime error 0xC0000005: Access violation reading location 0x00277000. I solved this error by storing the vector of pointers in the class that holds my Board instance, but I'm wondering why only this solution worked? Why couldn't I just have my vector of pointers in the same class that the instances of those objects were in?
C++ :: Get Value From String Containing Variable Name?
Nov 2, 2014As written in the title, I want to be able to extract a variable value from a string containing the variable's name. I know one can use associative containers such as maps but is there another more direct way?
E.g.:
int variable = 5;
string str = "variable";
// how do I get the value of 5 out of the string containing the variable name?
If I am correct, this is called 'Reflection', correct me if I'm wrong.
I know C++ has no inbuilt 'Reflection' class or anything like that so I was wondering if there is a workaround for this kind of thing or is there a library out there which can do this? (that's if I have the name right).
I have found a library called Boost Reflection which sounds like it could do this but I just wanted to make sure that reflection is actually what I am talking about and whether C++ can do what I'm trying to do? I'm not sure how.
C :: How To Store First String Into A Variable
Feb 11, 2013Im trying to write a program that reads in strings and decides if the 1st one is repeated. I cant figure out how to store the first string into a variable, and compare that variable to the rest of the inputted strings.
Code:
#include <strings.h>
#include <stdio.h>
int main () {
//Declared variables
int i;
}
[code]....