C++ :: Heap Sort Algorithm Crashing After 4100 Entries?
Nov 18, 2013
I developed the following heap sort algorithm code, and for some reason anytime it goes above 4100 entries, the algorithm completely crashes. It works perfectly up until that point but I can't see why it would crash?
void heap_from_root(MVector &v, int i, int n) {
int end=n,j=0;
// Identify the lowest root and how many sons it has. If it only has one son, set j=1.
if (n==1) { n = 0; j = 1; }
else if ((n-2) % 2 == 0) { n = (n-2)/2; }
else if ((n-1) % 2 == 0) { n = (n-1)/2; j=1; }
This program I'm working on accepts an array size from the user, prompts the user to store that many integers, sorts them from smallest to largest, and then searches for duplicates with a simple for loop. The ultimate goal of the assignment was to display duplicates in an array, and the rest of the functions are just how I decided to reach that goal.
Anyway, my program crashes if I choose an array size larger than 7. It sorts and displays duplicates perfectly with 7 or fewer arguments.
The exact moment it crashes is after I enter the final value it prompts me for, so it appears my inputsize() function and my inputarray() function are working, and the error may be in the arrsort() function. Code is below:
Code: #include <stdio.h> int funcinputsize(int); void funcinputarray(int [], int size); void funcarrsort(int [], int size); void funcdupe(int [], int size);
This compiles fine but when I run the .exe for the first time an error message comes up saying program has stopped working. If I run the program again without recompiling it seems to work as expected.
So i'm trying to implement the selection sort algorithm and it seems that the code is fine but...
Code: #include <cs50.h> #include "helpers.h" void sort(int values[], int n) { // TODO: implement an O(n^2) sort
[Code] ....
I keep getting these errors and i don't understand why:
/usr/lib/gcc/x86_64-linux-gnu/4.6/../../../x86_64-linux-gnu/crt1.o: In function `_start': (.text+0x20): undefined reference to `main' collect2: ld returned 1 exit status
I'm trying to implement the Merge-Sort algorithm. I only had the pseudocode for it and have some problems coding this into C.
I have only covered pointers recently and I tried using them, which did not work. I started with the code for the merge algorithm and only used a 10 element array, which was already divided into two sorted subarrays:
Code: #include <stdio.h>#include <stdlib.h> int main() { int a[5]={1,5,6,10,13}, b[5]={4,8,9,10,14},c[10], *i,*j,k;
[Code].....
This is the result that I get:
Code: 1 4 5 6 8 9 10 10 13 0
So I think the problem occurs because in the second to last loop i is incremented again, but the end of the array is already reached, and the compiler has no element a[6] to compare with *j in the last run of the loop. Is there generally a better way to implement Merge?
I'm tinkering with a serial quick sort algorithm. Normally I use qsort() but I wanted to test this.
Somehow I loose the highest number. I can't see where I drop it.
Code: // function to quicksort, leave them in front of qsort. void swap(float_t *left, float_t *right){ float_t temp; temp = *left; *left = *right; *right = temp;
So I have an insertion sort function implemented that sorts through an array, but I'm having a problem showing the correct number of comparisons to work.
Each time I'm checking a value with another, the counter should update.
For instance, having an array of 10 elements going from 10-1 should give 45 comparisons, but I'm getting 54 comparisons.
void insertionSort(int a[], int& comparisons, const int& numOfElements) { int j, value; for (int i = 1; i < numOfElements; i++) { value = a[i]; for (j = i - 1; j >= 0 && a[j] > value; j--)
I've written code for a selection sort algorithm to sort through a singly linked list, However, it only brings the smallest node to the front, but doesnt swap positions of any of the remaining nodes, even though they are not in order.
This program is sorting a randomized array of integers using the bubblesort algorithm.
I am trying to modify n correct the source code,so that the swapping of two values will be done by a function called swap values() by using call-by-reference but function should have as arguments only the two array elements that must be exchanged. (Note: do not pass the whole array to the function!) .We consider an array with the first element containing the number of elements in the array, followed by 10 randomly initialized integers (elements).
The code must sort the 10 elements in ascending order.
Compile: g++ -Wall sorting.cpp -o sorting */ #include <iostream> #include <stdlib.h> using namespace std; int main() { const int SIZE=10;
C++ sort algorithm or library that can take input of a bunch of rows of data and then sort rows by an arbitrary defined order of one of the columns ... i.e., sort rows by value of the first column in this order (boba bobc bobe bobx) etc?
So I'm going through and trying to do a recursive implementation of a Heap. I keep getting access violations for some reason on my sifts (_siftUp) - even though I'm trying to insert into sub[0] (currSize = 0 in the constructor). I don't think either of my sifts are implemented correctly, are they?
If I have an array, and want to make a heap tree out of it using make heap and sort heap, how would I do it? I'm struggling because I didn't take any course in data structure.
I tried googling stuff and I got to the following:
I know that memory addresses in the stack can contain either values or references to other memory addresses, but do these memory addresses also contain methods or are the methods themselves located in the heap?
The confusion comes from the fact that in C# a delegate variable can be assigned either a method's identifier, an inline function, a lambda expression, or a new instance of the delegate type with the method's identifier passed as an argument to the constructor. My guess is that assigning the method's identifier directly to the delegate variable is just a simplified way of calling the delegate type's constructor with the method's identifier as an argument to the parameter, something that the compiler handles for you.
But even in this last case, the delegate variable is said to point toward the method itself. In that case, does it mean that methods are stored in the heap, just as reference type values are?
I am creating a class that has a private array on the heap with a constructor that takes the size of the array and initializes it on the heap. Later I have to make a deconstructor delete the space and print out free after.In my code, I was able to heap a private array and make a deconstructor, but I don't know how to take the size of the array and initialize it on the heap. My guess is this:
int* size = new int();
Also when you initialize size on the heap, don't you also have to delete it too? If so, where, in the code, do you do that? Here is my code so far.
Class Student { private: int size; int* array = new int[size]; public: Student(); // Constructor ~Student(); // Deconstructor
[code]....
How do you make a constructor that takes the size of the array and initializes it on the heap
i want to write a c++ program to build min heap which gets above values from user. remember this program should not alloduplicate values to enter. it should discard duplicate values.
I recently posted a question related to creating a heap template class. The ultimate goal is to create a series of classes that serve a purpose that was overlooked in the Qt library that I need for my current project.
The current "end goal" is a PriorityQueue template that uses a comparer class which is inherited from a "template interface". Basically a pure virtual class template. Perhaps that is the mistake to begin with but hopefully not. (Is this a valid approach?)The problem I am getting is that when I compile the code, it says my derived comparer class is abstract.
I will include all related classes here. I doubt it is relevant but the templates and the classes based off them are in different namespaces.Here is the comparer "template interface":
// in global namespace template<class T> class IIMQOBJECTS_EXPORT IQComparer { virtual int compare(T& a, T& b) = 0; virtual bool equals(T& a, T& b) = 0; virtual bool isGreaterThan(T& a, T& b) = 0; virtual bool isLessThan(T& a, T& b) = 0; };
Here is the class that is supposed to be non-abstract but isn't recognized as such:
// in the application namespace AND IN SAME project that has the NetEventInfo class // all functions ARE defined/implemented in a cpp file class APPCORE_EXPORT NetEventInfoComparer : ::IQComparer<NetEventInfo*> { public: NetEventInfoComparer(); ~NetEventInfoComparer();
Basically, say i wanted to sum all the values enter for x. First, i ask the user how many x's there are, then create a "for" loop to ask for x1, x2, x3, .. xn. Then i want to know the cumulative total of x. How would i do this? This is the sample code i have made right now inside of my main function:
Code: int N; int I; int X; //This is where i ask for how many x's there are// }
I'm having trouble understanding how to get my phonebook to print out it's entries. If I just have one entry, it will correctly display it but if I have 2 or more, it leaves out chunks of that entry's data.
I'm creating a program that holds three arrays one for the persons last name, one for the points scored and one for the player number, now I've got all the arrays and everything done but I'm not sure as to how I'm going to delete an entry for multiple arrays.
It compiles just fine and it will add new entries and print the entries just fine but when I go to delete an entry it will delete it but it will mess up the one before it.
