C :: Cannot Use Array Name In Expressions

Nov 27, 2014

Code:

int main() {
char *arr[] = {"Hello", "World", "Good", "Morning"};
display(arr);
return;
}

[code]....

The code works fine and prints the 4 strings. Where i m riddled is whether "ptr" in display function is a pointer or a string ? If it's a pointer then what is the type of the pointer? If it's an array, then as per my understanding, we cannot use an array name in expressions such as ptr++ (K&R).

View 2 Replies


ADVERTISEMENT

C++ :: Regular Expressions Not Working?

Aug 25, 2014

I have this bit of code that I found here: [URL] and at first regex would work, but then when I hit "[]" it wouldn't. Here's the code:

#include <iostream>
#include <string>
#include <regex>

[Code]....

View 2 Replies View Related

C# :: Cannot Convert Lambda Expressions

Mar 31, 2015

I get the following error:

Cannot convert lambda expression to type system delegate because it's not a delegate type (on invoke).

The Second error is: Client.PrivateChat.txtReceive is inaccessible due to its protection level..

private PrivateChat pChat;
private void client_Received(Client sender, byte[] data) {
this.Invoke(() =>
{
for (int i = 0; i < clientList.Items.Count; i++) {
var client = clientList.Items[i].Tag as Client;
if (client == null || client.Ip != sender.Ip) continue;

[Code] .....

View 4 Replies View Related

C++ :: Use Boost / Regex For Regular Expressions?

Sep 5, 2013

So I need to use boost/regex for regular expressions. someone told me that it needs to be built. the first problem is boost doesn't tell you how to build it and the second is i did sudo apt-get install libboost something. I don't remember the exact name of the package. it installed but i dont know how i would build it when its installed.

View 2 Replies View Related

C++ :: Email Validation Without Using Regular Expressions?

Dec 11, 2013

writing a program for "Validating the e-mail id without using regular expressions in c/c++"?

View 4 Replies View Related

C++ :: Evaluating Logical Boolean Expressions

Jan 10, 2013

I am looking for a library to aid me in evaluating Boolean expressions. For example, i have an expression like this:

(1*(5+3)+9*65/5-(354*4565*5643+98) >= 12345) && ( 654*987+123 || (2345 > 23423 && 1 != 2)))

(It can also be much longer!) and would like to evaluate them to a true/false boolean.

There are tons of libraries to calculate the (numerical) result of a mathematical expression, but this is not what i want to do.

View 5 Replies View Related

Visual C++ :: Regular Expressions - How To Get Iterator

May 22, 2014

In order to parse mathematical expressions I am trying regular expressions and a recursive algorithm, but I have a problem with the four basic operations: +, -, *, /.

Trying to analyze a string like "a+(b+c)", if I use the pattern for a sum "(.+)+(.+)" the program matches it recognizing as subpatterns: "a+(b" and "c". How could I achieve the program to try also the other possibility?

I think that it would be great something like an regex_iterator which worked with regex_match instead of regex_search. I mean, an iterator that iterates over all the possible ways to match a given regular expression and a given string. This way I could loop through all these possibilities until the two subpatterns produced were correct mathematical expressions.

View 3 Replies View Related

C :: Shunting-yard Algorithm To Evaluate Expressions?

Sep 16, 2014

Can I use Shunting-yard algorithm to evaluate Expressions (arithmetic, relational, and logical) ?

View 8 Replies View Related

C++ :: Implement Program For Evaluating Infix Expressions

Dec 3, 2014

Also, can't use namespace std for this.

#include<iostream>
#include<stack>
#include<fstream>
#include<iomanip>
#include<queue>
#include<cassert>

[Code] ....

/* It will read in a infix expression from a text file.check if the parentheses in the input expression are balanced.convert the infix expression into a postfix expression and evaluate the expression.*/

int main() {
string expression;
string postfixExpression;
double result;
testBalanced();

[Code] ....

View 8 Replies View Related

C++ :: Mixed Expressions / Loops And Formatted Output

Feb 22, 2015

1) ask the user to input a mathematical expression in the following format:

NUMBER Operator NUMBER Operator NUMBER
Example: 17 + 15 - 3
Example: 2 * 3 - 4

How to output the answer of the users equation. Is there a function that includes all math operators (+,-,/,*)? Would i need to write each possible scenario using if statements?

View 2 Replies View Related

C# :: Join Tables In LINQ With Lambda Expressions

Dec 5, 2014

i have stuck in a join and i cant figure out where the problem is, i have those tables

public class Themes
{
[PrimaryKey, AutoIncrement]
public int Id { get; set; }

[Code].....

View 12 Replies View Related

C++ :: Overloading Addition And Comparing Expressions In A While Loop

Apr 28, 2015

I have two questions that are related to each other. The first one is about overloading the addition operator.

I have defined a struct as the following:

Code:
#include <iostream>
#include <string>
struct Sales_data {

[Code] ....

I then overloaded the I/O operators so I could print to the screen information related Sales_data.

Code:
// overload ostream in order for cout to work
std::ostream& operator << (std::ostream & out,
const Sales_data & cSales_data) {
out << cSales_data.bookNo << ", " << cSales_data.units_sold << ", "

[Code] ....

My first issue is with overloading the addition operator. Everyone works correctly except for std::cout << item << std:endl; will no not output the ISBN number only the units_sold and revenue when added together.

Code:
// addition operator rules
Sales_data Sales_data::operator + (const Sales_data & data2) {
units_sold += data2.units_sold;
revenue += data2.revenue;
return *this;
}

Now here is the code in its entirety

Code:
#include <iostream>
#include <string>
// Sales_data structure
struct Sales_data {
std:: string bookNo;
unsigned units_sold = 0;

[code] .....

After total = total + item;, I would like to print the total for this particular ISBN. However, I only get: blank, total units, total revenue where blank is where the ISBN would go but doesn't print after addition. My second question has to do with comparing the ISBN's of the books entered during the while loop. I would like to do something like

Code:
if (item_i.bookNo == item_i+1.bookNo) {
total = total + item;
} else {
std::cerr << "Books entered must have the same ISBNs" << std::endl;
}

Unfortunately, I cannot figure out how to set up a comparison of the bookNos. If I used #include <casset> in the overload + rule, it will immediately exit since I have no way to compare the ISBNs.

View 3 Replies View Related

C++ :: Evaluating Arithmetic Expressions Using Recursive Descent Parser?

Feb 25, 2013

I have the following code to calculate arithmetic expressions :

#include <iostream>
using namespace std;
using namespace std;
const char * expressionToParse = "6.5-2.5*10/5+2*5";
char peek(){
return *expressionToParse;

[code]....

The problem is that it does not work properly with decimal numbers for example it evaluates 6-2*10/5+2*5 = 12 which is correct but for 6.5-2.5*10/5+2*5 it returns 6 instead of 11.5 .

View 3 Replies View Related

C++ :: Create Array Of Playing Cards / Assign Values And Suits Then Shuffle The Array

Nov 24, 2014

I got this program to create an array of playing cards and assign the values and suits and shuffle the array. I'm at the point where I need to output the cards but I need to burn the first card by making it output "**" instead of the card. my cards[] is a constant so I can's assign the first card as such.

void showCards(const int cards[], int numCards, bool hideFirstCard) {
if (cards[0]) {
hideFirstCard=true;
cards[0] = '**';
} for(int a = 0; a <= numCards; a++) {
cout >> showCard(cards[a]);
} }

View 1 Replies View Related

C++ :: Accept Integer Array And Its Size As Arguments And Assign Elements Into 2 Dimensional Array

Jan 10, 2015

Write a program using user-defined function which accepts an integer array and its size as arguments and assign the elements into a two dimensional array of integers in the following format: If the array is 1,2,3,4,5,6, the resultant 2D array is

1 2 3 4 5 6
1 2 3 4 5 0
1 2 3 4 0 0
1 2 3 0 0 0
1 2 0 0 0 0
1 0 0 0 0 0

View 1 Replies View Related

C++ :: Write Function That Takes Array And Returns True If All Elements In Array Are Positive

Jan 21, 2013

Write a function that takes an array and returns true if all the elements in the array are positive, otherwise, it returns false.

View 6 Replies View Related

C :: Store Character Array In Reverse Order Then Display Reversed Array

Jun 14, 2013

The program should store a character array in reverse order then display the reversed array. I have also included in the code that will display the actual characters into the array as it loops through. So I know the characters are being stored, but why doesn't it display the entire string when I call it?

Code:
#include<stdio.h>
int main(){
char str[50];
char rev[50];
printf("Enter Desired Text: ");
scanf ("%[^

[Code] ....

Is it just my compiler?

View 5 Replies View Related

C :: Parsing Char Array To Array Of Struct To Process Packets

May 28, 2013

I wrote this simplified version of a program i am writing that parses data in UDP packets. In the process of doing so i pretty much answered all my questions and fix all the problems i was having.

decodeSystemMap function will be in loop, and will proccess packets that have mostly the same data, only a few items will be added or changed or deleted.

whats the best way to check if there are any new, deleted, or removed items in the packet and only modify those?
Is there anything unsafe / dangrous about the way the code is now?

Code:
/* * File: main.c
* Author: david
*
* Created on May 23, 2013, 11:57 AM
*/

#include <stdio.h>
#include <stdlib.h>

[Code] ....

View 4 Replies View Related

C :: How To Make A Function Read From Array A But Put Select Parts In Array B

Jul 30, 2013

im trying to read in 1 array and get 2 as outputs from 3 different functions.my read array is easy enough were im getting confused is how to read that array, separate it and take out only the parts i want and place them into a 2nd, then again a 3rd array.i have the following so far:

Code:

#include<stdlib.h>#include<stdio.h>
#include<unistd.h>
#define SIZE 10
}

[code]....

this compiles without a complaint, but when i go to run it no longer responds after taking the 10th element (well 9th if counting from 0).I think i have the if correct for the even odd section, but when i try to populate B or C array with the output of that if statement from A is were i think things are dying...

View 12 Replies View Related

C++ :: Storing Numbers Into 2D Array - Invalid Types Int For Array Subscript

May 17, 2014

#include <iostream>
#include<fstream>
int decryption(int);
int multiply(int,int[][2]);
using namespace std;
main(){
int n;
ifstream inFile;
inFile.open ("out.txt");

[Code] .....

I was trying to store numbers read from a text file into 2D array but I am getting the error above.here is where the error occurs:

line 33: cout<<m[i][j]<<" ";

View 4 Replies View Related

C++ :: Using Loop To Process Array Of Characters Starting From Beginning Of Array?

May 3, 2014

Assume you want to use a loop to process an array of characters starting from the beginning of the array. You want the loop to stop when you read the null terminator character from the array. Fill in the loop test condition that will make this work correctly.

index = 0;
ch = array[index];
while ( _____________________________)
{
// process the character
index++;
ch = array[index];
}

View 1 Replies View Related

Visual C++ :: Reading Into Array / 2d Array From Mixed Text File?

Jan 18, 2014

I know to read a strings into array and tables.. what is they are mixed up?? strings are just names ( 3 characters) and there are bunch of table.. the max size was set to 60

ex. text file

JES
DAN
JEN
.
.
.
01010101
10010101
RAM
JET
01010010
10100101
.... and so on

should i use a while loop?

View 10 Replies View Related

C++ :: Multidimensional Array - Moving Whole Int Array Row As A Single Unit?

Feb 27, 2013

I have a multidimensional array that runs parallel with a string array

Lincoln 120 300 400
Parks 100 500 250
Shakespeare 0 30 50
Ghandi 250 100 40
Ashe 300 50 175
Rodriguez 87 118 320
Curie 284 0 112

I need to sort this and I know how to do it. But I need to sort it again with the highest value in the first row and keep all information in that row paired with the name . So

Lincoln 120 300 400
Parks 100 500 250

Parks 100 500 250
Lincoln 120 300 400

I need so swap this whole rows. I'm using dynamic array. So my question is Do I have to do a bunch of temps to move them? Or is there a way to move the whole int array row as a single unit?

View 3 Replies View Related

C++ :: Why Can't Static Array Copy Values From Dynamic Array

Mar 13, 2013

But it can the other way around

Code:
static_Array= dynamic_Array;
dynamic_Array = static_Array;

The second statement works and i'm able to print out both arrays with equal values but with the first

[code] static_Array = dynamic_Array;I get incompatible types in assignment of 'int*' to 'int [7]' is the error I get [/code]

View 2 Replies View Related

C :: Print Values Of Array From Function By Passing Array?

Nov 1, 2014

I wanted to print the values of a array from a function by passing the array as well as the number of elements to be read. For a single dimensional array, this is how i have written it. It's pretty straight forward. I want to read 5 elements from the 5th element in the array.

Code:
#include<stdio.h>
void display(int array[],int size) {
int i;

[Code]....

With this code I want to print the five elements from the element present in [0][4].

But shows an error that

Code:
D:BennetCodeblocks CLearning CSingleDimentionalArray.c||In function 'main':|
D:BennetCodeblocks CLearning CSingleDimentionalArray.c|18|warning: passing argument 1 of 'display' from incompatible pointer type [enabled by default]|
D:BennetCodeblocks CLearning CSingleDimentionalArray.c|2|note: expected 'int (*)[10]' but argument is of type 'int *'|
||=== Build finished: 0 error(s), 1 warning(s) (0 minute(s), 0 second(s)) ===|

I know when you pass a array as an argument it gets decomposed into a pointer, but with a multi-dimensional array this is not the case. how this works for mult- dimensional array's?

View 3 Replies View Related

C++ :: Passing 2D Array To A Function Where Size Of Array Is Not Known At Runtime

Jun 27, 2014

I'm wondering if it is possible to pass a 2d array to a function where the size of the array is not known at runtime.

I've tried

function ( array[][6] ) ;

But the size of the array has to be constant so it cannot be declared later.

I've tried using a template but you still have to declare the size of the array at runtime. Is this even possible at all?

The only other way I can think of is using a dynamic 2d array but how to create one and manipulate it.

View 2 Replies View Related







Copyrights 2005-15 www.BigResource.com, All rights reserved