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).
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.
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.
/* 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();
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?
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.
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.
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 .
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]); } }
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
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?
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 */
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:
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...
#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:
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]; }
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
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?
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?