I have the following function I would like to convert to work with std:string. I don't understand QT strings at all.
Code:
void FromHexString(const QString &hexText, void* pData, int dataSize) {
for (int i = 0; i < hexText.length(); ++i) {
bool ok = false;
((uint8_t*)pData)[ i ] = hexText.mid( 2*i, 2 ).toInt( &ok, 16 );
}
}
I need a large string vector for file content manipulation.
v1.max_size() gives me 153 391 689.
But if I make a test by looping a vector pushing back strings it crashes around 16 - 26 000 000 though I still have a lot of ram (1GB left).
How come and why isn't vector size limited by ram instead?
I'm VERY new in programming and I'm having trouble converting an integer to string. I need to create a function for a programme I'm working on for my school. My problem is that i am only allowed to use the libraries stdio.h, time.h and stdlib.h as well as printf, scanf, system, srand, time and rand. If I was allowed to use itoa or pointers it would be easier but i am not.
View 4 Replies View RelatedThis was an exercise from a book (convert a character string into a floating point value). It seems to work with both negative and positive decimal numbers.
It basically get each digit from the string multiplies by 10 to hold the place, and then adds the next to the result, if that makes sense.
Then determines where the decimal and null character are to figure out what to multiply by (1/1000 or whatever) to determine where the decimal should go. The variable names dealing with this part of the program aren't accurate names right now.
My question is, the output, is always putting 6 zero's. So if the argument is .95, Ideally the output should say .95 and not .950000, even though the value is still correct.
I know there the %.2f to determine the amount of decimals, but the amount of decimals in these instances would be varying depending on the argument sent to the function.
So, if 600.158 was sent as an argument, only 3 decimals would be displayed, as opposed to two from the previous example. Is there a way to do this?
Code:
// Function to convert a string to an integer
#include <stdio.h>
double strToFloat (const char string[])
[Code].....
Any really simple way of converting the following float to a string so I can take strlen()?
float a = 53213421;
strlen(a)?
I have looked up solutions but they are either too long or they confuse me.
I am trying to convert some chars to UTF-8 strings...
Example:
std::string gethex(char c) {
/* EXAMPLE
if (c == 'é')
return "%c3%a9";
I need a function that converts chars like "á, é, í, ã" to UTF-8 hexadecimal strings...
*/
}
[Code] .....
[URL] .... does it. Choose UTF-8, type some character and click 'Url Encode'.
As a part of a program I am supposed to write, I would like to receive a string from the user (for example: "Hi my name is Joe").
obviously, the string is inserted to an array of chars (arr[0]='H', arr[1]='i', arr[2]=' ',... and so on).
What I would like to do, is to put each word separately in each array cell (for example arr[0]='Hi', arr[1]="my"..., and so on). How can I do this? (I can not use any functions, unless I write them myself).
Any simple program that uses tolower to convert strings into lowercase? Or simply just the general syntax of tolower pls. Can find it in google.
View 5 Replies View RelatedI understand most of program below. Essentially, we have strings that we want to convert from hex values to decimal equivalents. We check if first two characters of string are 0x or 0X, which signifies hex format. If our hex string consists of solely digits like 0x25, then the processing is simple. We take the digit assign it to answer variable, and for each additional position in the hex base-16 system, we multiply the digit by 16.
Now if the hex string is something like 0x2A, then for 'A', the hexalpha_to_int() function is called, since we are able to find 'A' in the hexalpha string, we take the value of 'A', which is ascii 65 divide it by 2 and add 10 to it: 65/2+10=42.5. This doesn't make sense. What is the purpose of this logic right here: 10 + (i / 2).
Code:
#include <stdio.h>
#include <stdlib.h>
int hexalpha_to_int(int c){
char hexalpha[] = "aAbBcCdDeEfF";
[Code] ....
i need a function that will work for both dynamic and static implementations of a function to get the transverse of a matrix. so far, i have this
Code:
matrix transpose(matrix m)
{
int row, col;
row = m.com_dim;
col= m.row_dim;
}
[code]....
this works well with my static implementation, but when i try it in dynamic it gives me errors. the function has to be the same for both dynamic and static implementation
puts(pd) does not give any output in the below code. Also, the first puts(ps) does give an output, but the second puts(ps) after "while" does not give any output.
Code:
#include <stdio.h>
int main()
{
char source[50]="Alice has apples.";
char destination[60];
char *pd, *ps;
}
[code].....
Why it's not working and how to make it work?
Code:
string str = "hello" + " *** ";
I have a problem set where i have to read in numbers from a file as strings, convert from strings to integers, and pass the integers into a linked list, where each integer is a node. This is what I have so far:
Code:
# include <stdio.h>
# include <stdlib.h>
# define MAX_INT_SIZE 10000
typedef struct integer BigInt;
struct integer {
[Code] ......
i'm right now using C, IO is done via ncurses, but that won't affect the following problem, i think. The relevant code is:
#define SIDEBARWIDTH 27
//...
typedef struct {
[Code]...
surprisingly this works, now the new 3rd outputline is correct again. So it seems that the printcommand has some troubles with accessing the struct here. Not sure if that might be ncurses fault. Still feels odd.
I have this:
string input;
unsigned short choice;
...
istringstream valid(input);
...
if(!(valid >> choice))
{
//some error
}
Ok. My code is almost 1000 lines, and I have splited some functions in headers. But the same function doesn't work:
template <typename T> bool valid_input(const string& input, T var)
{
istringstream valid(input);
return (valid >> var);
}
You can check it here: [URL] The output is correct, but in my machine with C++11, MinGW 4.8 (64 bit in a 64bit-Windows8), the output is incorrect. Why?
If you want more specific info, the problem is that I use input, I think. I use std::getline(std::cin, some_string).
Ok, so I'm writing this code and when I build it keeps saying cannot implicitely convert type int to string even though I declared my variables as string. Why is it giving me this error?
private static string Repair()
{
string result="";
string beep;
string spin;
Console.WriteLine("Does your computer beep on startup?:(y,n)");
[Code]...
This is my code for submitting students but when i use search function the course member is empty
Code: #include "windows.h"
#include "iostream"
#include <io.h>
#include <sstream>
#include <conio.h>
#include <stdlib.h>
#include <iostream>
#define SIZE 5
using std::cout;
using std::cin;
using namespace std;
int menu();
[code].....
i am facing some problem with qsort() function it work well if the last element of array is larger then the 2nd last element. But in case if last element of array is smaller then the 2nd last it will sort the whole array and remains the last as it is. For example
Code:
int group_id_local[max_j]={2,1,4,5};// it work fine, output should be {1,2,4,5} but if i have this one
int group_id_local[max_j]={2,1,4,3};
// output should be {1,2,4,3}
/* COMPARE FUNCTION FOR USING QSORT()*/
int cmpfunc (const void* a, const void* b)
{
if (*(int *)a < *(int *)b) return -1;
if (*(int *)a > *(int *)b) return 1;
return 0;
[Code]....
why it will not sort the last element?
If yes then how?
View 6 Replies View RelatedI have to do a BST project for school and I am almost there. Here is the code:
BINARY_SEARCH_TREE.cpp
#include "stdafx.h"
#include "genBST.h"
#include <iostream>
using namespace std;
[Code].....
When I run the program, it compiles correctly but does not give any output. I'm not sure what else to do. I've tried changing up the code in nodeCount(), leafCount(), NodeCount(), and LeafCount(). I've tried adding a count variable to both nodeCount() and leafCount() but that didn't work. If I fiddle with the functions, I get a whole mess of errors. Currently, the code is stable but just won't output what I want it to.
I'm having trouble with getting a sine function to work. All variables are defined earlier in the same section. I have the code in a button (where I figured it would go) but I get the following error:
WindowsFormsApplication2.Math does not contain a definition for 'Sin'
For reference, I am using Microsoft Visual Studio Express 2013, and am coding a Windows Forms Application.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
[Code] ....
I've tried other functions as well (abs, sqrt, etc.) to no avail, as Math only seems to pop up with two options: Equals and ReferenceEquals.
We have to make a function integrate to work with the other functions given. I had it working before but I would only get all -4 as my answers but only the first one should be -4. what should more or less be put in my integrate function?
#include <iostream>
using namespace std;
typedef double (*FUNC)(double, double, double) = (line, square, cube);
double integrate(double FUNC, double a, double b){
for(int i=0; i<a && i<b; i++){
FUNC = a-b;
[code]......
void Quicksort(int info[],int left,int right){
int pivot = left + (right - left)/2;//it is the middle (will change sometimes but will end up in the middle
int temp;
while(left<=right){
while(info[left] < pivot){
[Code] ....
This is my quicksort function. I have tried a lot of things but I am trying to get it to work to sort all the details I have stored in an array by there age. This is how I have entered the data.
void DataEntry(Details info[],int size){
int x;
int i;
i=0;
cout << "How Many Entries Would You Like to add";
[Code] ....
I am stuck on what to do with it
heres the function:
string ToString ( const char * format, ... )
{
char buffer[256];
[Code]....
these function do the same of the sprintf() function. but instead we use a variable for add the result, i want to return the result. when i use it:
string f;
f=ToString("hello world");
gives me several errors:
"error: crosses initialization of 'std::string f'"
"error: jump to case label [-fpermissive]"
I am using Visual Studio 2008. I just wonder if there are any library function in Windows SDK or MFC, or from third-parties, that can convert a UTF-8 string into Windows Unicode string(used in CString object).
Can MultiByteToWideChar or ATL String conversion macro like A2W to the conversion?
Code:
struct lista* del(struct lista* p, char* path1) {
char model[MAX2];
int len;
char ch;
printf("Type model.
[Code] ..... t
This function should delete each element in the list which is the same as this one typed by user. There are no errors, but function doesn't work. It deletes something, but not this element which should.