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;
[Code] .....
I have written this code to arrange user input array in an order.
//Recursive Quick Sort
#include<stdio.h>
#define ARRAY_SIZE 10
void quick_sort(int array[], int len)
}
[code].....
I've been trying to implement a quick sort algorithm for linked list but when i try to run it with 1000000 values my compiler tells me its running too long and ends up not finishing. However when i run it with 10 values it seems to work fine.
Is there anyway to improve this run time?
Code: struct listnode *quicksort( struct listnode *data ) {
size_t length = 0;
struct listnode *pivNode, *temp = NULL, *low = NULL, *high = NULL, *ltail = NULL, *htail = NULL, *prev = NULL, *end = NULL, *next;
// Get length
for( struct listnode *cursor = data; cursor != NULL; cursor = cursor->next ) {
length++;
}
[code].....
My whole code is included below, although what is really important to me is only the first two functions, the quicksort and the partition...Whenever I build this program, it keeps returning an error for the calling of the partition function, citing that the first variable is in an improper format... I don't know why it's not working though..
Whole Code:
#include <iostream>
#include <string>
#include <algorithm>
using namespace std;
template <class T>
void quicksort(T arr[], int start, int end)
[code]....
I am trying to sort a linked list using quick sort in C. Here is my code--Actually, first I am inserting data in the list from a file. For a small file, it's working fine. But for large file it's just not working.
Code:
struct node {
int data;
struct node *link;
struct node *plink;
[Code] .....
i can't seem to get this merge sort to work. running through gdb though;
Code:
*Filename: mergeSort.c
*Usage: This implements merge sort algorithm to sort and array of numbers.
*/
#include <stdio.h>
#include <stdlib.h>
}
[code]...
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?
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--)
[Code] .....
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.
Input list: 3 6 17 15 13 15 6 12 9 1 2 7 10 19 3 6 0 6 12 16
Sorted list: 0 6 17 15 13 15 6 12 9 1 2 7 10 19 3 6 3 6 12 16
Code:
#include<stdio.h>
#include<stdlib.h>
struct node{
int val;
struct node *next;
[Code] ......
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; }
[Code]...
I am trying to code a merge sort algoritm, using my knowledge of C++. I have made some code but it is not working. It is giving some random results.
Code:
#include <cstdlib>
#include <iostream>
using namespace std;
void print(int *niz) {
[Code] ....
# include <iostream>
# include <vector>
# include <cstdio>
# include <algorithm>
# define inf 100000
using namespace std;
int cnt;
vector<int> merge( vector<int>& left, vector<int>& right) {
[Code] ....
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;
[Code] .....
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?
View 1 Replies View RelatedCan I possibly get a better implementation of a prime number detecting algorithm than the one I already have below?
Code:
#include <cstdio>
#include <cstdlib>
int main() {
int no, high, low;
int divisor;
[Code] .....
I'm writting an algorithm which equals to std::to_string. The inttostring part is fine, and the decimal_part too. But when the number digits > 5, the program loops infinitely.
#include <iostream>
#include <string>
#include <algorithm>
[Code]...
In this code, the program runs ok. But try to add a 5 at decimal_part. What should I do to get this 'decimal_part' ok?
I am creating a website in which a user can upload an image to a sql database. It is converted to varbinary and then read into an Image object using a http handler to convert it to an image. this all works fine. When I open an popup window I am reading data from specific rows into textboxes, thus when the user confirms any changes the rest of the data stays the same. How can I hold the Image and redisplay it when returning to the main page after closing the pop up. It currently sets the image in the database to null as the file upload object has not been given a directory location all the time. This is my attempt at reading the image from the database and then reapplying it if the file upload is empty
private void ChangeFilm(int id)
{
SqlConnection con = new SqlConnection(my settings go here);
con.Open();
[Code].....
Here's the code I'm writing:
Code:
#include <stdio.h>
#include <stdlib.h>
char* getTeamCode(char* team);
[Code]....
Why the placement of the code on line 21 above matters.
It grabs the correct string just fine. If I write a printf just below it, it prints the string it should correctly. However, if I do a printf of the string OSUteamCode below the fopen call on line 23, it prints blank.
So the first thing I did was move it below the fopen line. It worked, finding and outputting the first game in "game.csv" just fine, but not the other 11. Debugging with printf shows that the contents of OSUteamCode again disappear after the fopen call in the addLineCSV function.
I'm not understanding why that happens. The only thing I can figure is there's something going on with the file I/O commands that I just don't understand, but I can't find anything online that explains what that might be.
I have to made a programme which will search for given number and it must work in O(log(n)). The problem is that this programme beside finding this number have to find how many times this given number is used in this sequence.
Sequence is from lowest to highest only one possibility to use binary search algorithm
For example when we have squence
-1 -2 3 3 3 3 4 5 6 7 7 8 9 9 9 9 10
The numbers we need to search are
1 , 3 , 7 , 9 , 11 , 12
The answer is
0 , 4 , 2 , 4 , 0 , 0
So we need to find the sum of used number in sequence.
I have written algorithm Code: int start = 0;
int end = sequencelenght - 1;
int mid = 0;
/// Binary serach
while (start<=end) {
int mid=(start+end)/2;
if (sequence[mid]==givennumber) {
[Code] .....
As u see i search for given numer with binary with O(log(n)) but when i have to sum the duplicates the only good way i see is using loop to right and left but this have got log(n) specification (because when sequence would be for example 7 7 7 7 7 7 7 7 7 and given number to search will be 7 this will be O(n) loop).
How would look the most optimal algorithm look for this exercise? I mean O(log(n)) the fastest algorithm....
So I have this set
13
14
24
31
62
35
36
42
13
44
62
now using sba or Set Based Algorithm I have to pair it out and towards the end find the size of the resulting set
#include <iostream>
#include <set>
int main()
[Code]......
this is the code just reads the edges that's 3... that is when we input the code. But what if its in a file? how do I read from there and show the paired count and the time taken?
Also I have the file that works and reads any txt file..but how do i get the code from it?
[URL]
this is the file..you have to run it as ./edgecount for it to work
I am working on a project that uses a web service to extract a PNG image from a web server and save it on a local machine. It's done via a system call. I can get the output of the system call to a FILE but it appears to be losing data, most notably the PNG chunk names (IHDR/PLTE/IDAT/IEND, notably). (Unfortunately piping the output to an exterior file does not work through a system call.) The end result is ~6KB smaller than the file I am intending to retrieve.
This is the code I'm using (adapted from other material I found via searches here):
ofstream png;
png.open(/*outputfile*/, ios::binary);
FILE* fp = _popen(/*SYSTEMCALL*/, "rb");
string responseString;
if(fp != NULL) {
char a[100];
while(!feof(fp)) {
fgets(a, 100, fp);
responseString += a;
}
}
_pclose(fp);
png << responseString;
Am I missing something or just doing it wrong?
I know that returning to main() is not a good idea but how will I loop the program to go back to the position selection when the voter is done voting for the last position.
when I run the program it seems fine. getting the votes from President to PRO Position is fine. The problem is how will the next voter vote without losing the vote (tally) of the previous voter?
FLOW:
SELECT POSITION (a-e) ---> SELECT A CANDIDATE (a-c) ---> (this goes on until the position of PRO) ---> ( then go back to the POSITION SELECTION)
After every vote there is a case statement for which I can choose to vote for the next position, quit, or show results (and after showing the results it will go to the next position to vote)....
#include<iostream>
#include<string>
#include <conio.h>
using namespace std;
int pca=0,pcb=0,pcc=0,ptv=0;
[Code] .....
I have an school assignment that asks me to measure the most famous sorting algorithms for performance in terms of number of steps and CPU running time. ( Here I'm testing for running time)
I decided to test for bubble sort first:
#include <iostream>
#include <ctime>
using namespace std;
void bubbleSort(int ar[], int size) {
int temp;
[Code] ....
So basically what I want to know is:
1. Is this clock function giving the correct CPU running time?
2. Is there any way to write code that would measure the number of steps for each algorithm?
3.I need to test it for number of integers=100 then 200, then 300... Well you get my point, and I don't want to have to actually input 200 numbers with my keyboard. Is there any way to generate as many entries as I want?
I have this code(homework) i've been working on for several days i couldn't fix this error.
Question is: to write a sort program in c . Ineed to ask user for how many numbers to be sorted(n) ask again for values. The approach of sort is this:
1- store n in temporary var (temp)
2- search for largest number in array (0 until temp-1)
3- switch the fied that store largest with field indexed by (temp-1)
4- temp-- (decrement)
5- repeat steps 2 to 4 until temp is 1
the program then prints the numbers of array on screen in one line. I also should use a function getMax(int *list , int n) that determines largest value and returns its location in that array
list : is the array
n: number of elements
Code:
#include<stdio.h>
int getMax(int *list, int n); //definition of getMax function
int main(void) {
int n,i;
[Code] .....
so i tried to sort this array
Code:
input 2 7 9 4 3 1 6 5
The out put should be : 9 7 6 5 4 3 2 1
instead it prints : 7 9 2 4 3 1 6
When I run the program the first int that is stored in the array keeps changing to -858993460.
#include <iostream>
using namespace std;
int main() {
int i;
int j;
int testScore[5];
int count;
[Code] .....