Questions tagged [binary-search]
The binary-search tag has no usage guidance.
96 questions
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PSet 3, binary search implementation
I'm struggling with implementation of binary search in PSet 3, and my code can't quite get past check50.
Here's my code:
bool search(int value, int values[], int n)
{
// TODO: implement a ...
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pset3 binary search , problems with check50
i have tried a lot but cannot find the meaning of the last two errors of check50 please help
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Recursive Binary Search Exit Code Errors
I wrote the following recursive binary search function. No matter which exit codes I use (e.g., true, false, 1, 0, -1, "Swedish Chef"), I fail at least two of the checks I need to pass. The code ...
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Trouble with binary search
Using gdb, I found the problem is when
the left_values is not there because if I try print left_values right after declaring it, it tells me No symbol "left_values" in current context.
after ...
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binarysearch no errors from compiler, but only spews out gibberish , anyone got an idea?
To make it more readable i thought this time i will just post the link to my helpers.file. The bubblesort worked and the linary search before too.
Maybe i did something wrong in the implementation of ...
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Binary search algorithm only works for smaller arrays
I can't figure out what I'm doing wrong. My algorithm works for smaller arrays, but once the number of values increases, the program stops and I have to hit Ctrl + C. I thought maybe it was an issue ...
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pset3 binary search , shows errors in check50
i don't understand acc. to the algorithm it should work correctly , but it doesn't
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binary search pset 3 pointer to integer error
I am trying my hands on binary search. I get those pointer to integer errors :(
Can sonmeone more experience give me a hand ?
bool search(int value, int values[], int n)
{
int first=0;
int last=n-1;
...
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What if binary search's split was not in the middle, but in a way the left side is twice as long as the right side?
How would the time complexity change if the binary search's split was not in the middle ((left + right)/2), but rather in such a way that the left side is twice as long as the right side?
So we check ...
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Pset3 Binary Search problems
I have tested the code presented in the picture and find this function always returns false no matter what number you search.There must be a problem in it but I can not see it!! Can anyone help me ? ...
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Question about binary search. Please help!
https://www.youtube.com/watch?v=5xlIPT1FRcA&t=200s
I am struggling to understand how to implement binary search. According to the video, there are 14 numbers in the array. Then he goes on to ...
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Pset 3 - Binary Search - clang: error: linker command failed with exit code 1
When I compile, with "make find", the following code:
I get:
So, if I'm interpreting this correctly, there's an undefined reference to search on line 58 of find.c, which is -- if (search(needle, ...
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when to search in binary search right, when left?
in the binary search algorithm:
If no items
Return false
If middle item is 50
Return true
Else if 50 < middle item
Search left half
Else if 50 > middle item
Search right half
like can we do the ...
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Purpose of sizeof(book)/sizeof(string) in lectures' binary sort?
string book[] = {
"Chen",
"Kernighan",
"Leitner",
"Lewis",
"Malan",
"Muller",
"Seltzer",
"Shieber",
"Smith"
}
int main(...
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how effective would it have been to use an array for the dictionary?
I just completed pset5 using a trie, but I'm curious about other methods.
How effective would it have been to load the dictionary into an array and then use a binary search function to locate words ...
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Code won't progress unless user inputs a number
I was writing a binary search function before finishing lecture 3 because I wanted to do some practice on my own. I was using scanf, which I had looked up, as I wanted to learn how to code without the ...
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find problem with my code - CPU overload
I cannot figure out what is wrong with my code.
/**
* Returns true if value is in array of n values, else false.
*/
bool search(int value, int values[], int n)
{
// ensures that the n is non ...
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pset3 find less comfortable if else expression result unused
I do not understand why I get an errors:
error: expected ';' after expression
else (value > values[l])
and
helpers.c:40:21: error: expression result unused [-Werror,-Wunused-value]
...
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CS 50 - pset3 find helpers: Why do binary search and selection short not work?
the command line yells at me but I cannot find out why. Any ideas what could be wrong?
Here is my code:
/**
* helpers.c
*
* Helper functions for Problem Set 3.
*/
include
include "helpers.h"
/...
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PSET3 find having trouble. Can someone help?
For some reason bubble sort is not working. Can someone help.
binary search bool search (int target, int array[],int length)
{
int end = length-1; int start = 0;
while (array[start] < ...
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pset3: sort and search work in separate files, but my helpers.c doesn't work
I dealt with sorting in a separate file first, and then I dealt with searching in another file. They seem to work okay or at least worked for the numbers I feed in, but when I put them in helpers and ...
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For pset3 binary search will this code work?
Here is the code .
bool binary_search (int target, int array[],int length)
{
int end = length-1;
int start = 0;
while ( array[end_num]- array[start_num] > 0)
{ ...
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do I need recurson for binary search?
Also do I need recursion for any of the pset3 solutions?
If yes any good sources on recursion. There was a quick example in lecture 3. Will that suffice? Preferably a video. I realize I could just ...
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Find.c - Binary Search probable integer overflow
Here's the gist: https://gist.github.com/Securiteru/a83e4f1a028acd0b1013def793b5dcdc
And the output:
... 60697 61151 61190 61275 61460 61608 61618 61746 61750 61822 62111 62178 62183 62311 62448 ...
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Pset3, Find, search
In "Find" problem, something seems wrong with my binary search Algorithm, because in check50, helpers.c wouldn't compile, I tried to compile it, then it gave me this weird error:
clang -fsanitize=...
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pset 3 binary search help
I am working on pset 3 for cs50 on edx, and I'm having quite a bit of trouble with the binary search problem. My program worked fine when I tested it with a linear search (so I think the problem isn'...
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Segmentation Fault pset3 for Find
I'm getting a segmentation fault error and I can't figure out why.
void sort(int values[], int n)
{
// TODO: implement a sorting algorithm
for (int i = 0; i<n; i++)
{
if ((n!=i+...
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PSET3 Binary Search Function Infinite Loop
When I try running find.c inputting:
./generate 1000 50 | ./find 127
it should return that the value (127) was found, however when I do it with my code, it seems to create an infinite loop.
Also, ...
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Pset3 helpers.c
i'm stuck in binary search. Check50 doesn't pass all the checks and it doesn't find the needle, I feel like the algorithm i have implemented is correct but it doesn't work. I've been stuck in this for ...
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Binary Search for helpers.c
so as the title suggests I am having some trouble with my implementation of binary search. So based on the logic shown in the lecture, I think my implementation is fine, indeed it works for the cases ...
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Binary Search Pset 3 help
As my question is titled, I would appreciate help with my binary search, shown below. Currently, the search will always return false. I am almost certain that my sorting algorithm is correct, as it ...
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Result doesn't match expected output
I just finished the helpers.c pset, where you have to implement a counting sort and then a binary search. I havent made it recursive yet but it works in all of my own test cases. I also ran the ./...
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pset3: search (am I in the right track??)
bool search(int value, int values[], int n)
//search for middle lists
if (value == values [n / 2])
{
return 1;
}
//number greater search left
else if ( value > values[n / 2 ])
{
search(int ...
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Pset 3 Recursive Binary Search problems - Always returns true
I have tried almost everything and edited my code a hundred times in search of an answer. It seems that whenever I run the program (find.c) the result always resolves to true. Not sure where the ...
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Odd bug for Find
I've been working of the find (problem set 3) for 2 weeks and I'm just stuck.
I already have the design etc worked out but there is a bug that I seem to be missing.
So the problem is that when I run ...
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cs50x pset3 find - Need help with the counting sort
can someone please look at my code and tell me where I went wrong with my counting sort algorithm (Or binary search algorithm, if that's where the problem lies...?). Please and thank you.
Binary ...
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C: Binary Search searches and finds but incorrect exit code
This code is finding all the numbers correctly. Only problem is it's throwing error of "\ expected an exit code of 1, not 0" when the number is not present. Help would be appreciated.
bool search(int ...
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Advice re: Binary search - various issues
I need advice as to what to change in this code to make it work. I am new at this so I need specifics, please. Please, no opinions on whether it's trash or what mark you would give if grading it. That ...
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C: Pset 3: Binary Search - 'expected an exit code of 0, not 1' (not finding n)
This is an attempt at binary search. n is the user input (from main script).
This code compiles but doesn't find the needle in the haystack. I'm a bit lost and would welcome assistance.
bool ...
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please help me with this binary search
for some reason this binary search code keeps returning true, when providing the haystack from generate.c, even if the "needle" isnt there. when manually inputing the haystack, the code runs perfectly....
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Pset 3: Find (more comfortable) - child exited with status 255 & exits with wrong code
I ambitiously decided to try the more comfortable version of this task, although I'm very much "less comfortable" with regard to any computer skills... Before I give up, I'd like to ask you what's ...
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PSET3 \ expected an exit code of 0, not 1 (find.c)
I successfully built my program and went on to check it using check50 only to discover this
:) helpers.c exists
:) helpers.c compiles
:) finds 42 in {42,43,44}
:) finds 42 in {41,42,43}
:) finds 42 ...
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Pset3 Find - Not sure what is wrong with helpers.c code
I am not sure what is wrong with the code. It seems to work on some of the criteria when using cs50's check50, but does not work on others. There also does not seem to have a pattern about the wrong ...
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Recursive function problem - return value
I am getting the following error below. It has to do with my binarySearch function.
helpers.c:149:1: error: control may reach end of non-void function [-Werror,-Wreturn-type]
}
^
However I have a ...
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Pset3 helpers.c while loop exiting unexpectedly
I am trying to implement a binary search algorithm. However, my while loop isn't working as expected. Having used printf and debug50 with a list of 100 numbers, it seems that the while loop only gets ...
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Binary Search pset3
bool search(int value, int values[], int n)
{
int found = 0;
int notfound = 0;
int minindex = 0;
int maxindex = n;
int midindex = 0;
do
{
midindex = (minindex + maxindex) / 2;
if (minindex &...
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helpers.c passes check50 but fails ./generate 1000 50 | ./find 128
check50 gives me all smiles, but when I run the test code ./generate 1000 50 | ./find 127 or 128 they both return "Found needle in haystack". How is that possible? And also, can I be sure my code is ...
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pset3: When testing binary search code, how do I print when needle is found?
I would like to test if my binary search function is working correctly. I have created an array that is passed into a working bubble sort function. Printing the sorted array works just fine, all I ...
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Pset3 recursive binary search function - check50 gives me four :( and I don't know why
I would be really grateful if someone could offer me a hint as to where I'm going wrong with this - I've been stuck for a couple of days now. When I work through the code step by step on paper it ...
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What's wrong with my binary search code?
I thought I got everything right but when I checked my code with check50 it shows the following errors:
:( finds 42 in {42,43,44}
\ killed by server
:( finds 42 in {40,41,42}
\ expected an ...
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