Check for balanced parentheses using stack
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- Опубликовано: 27 окт 2013
- See complete series on data structures here:
• Data structures
Algorithm or program to check for balanced parentheses in an expression using stack data structure. This is a popular programming interview question.
See source code here:
gist.github.com/mycodeschool/...
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I clearly understand this subject now. I saw this for free and am in debt from school for something they couldn't teach. The irony. Thanks for the lovely video!!
H
the best data structures video on the internet i've ever seen. thanks for the clarity and understandability even 9 years later. hope you're okey
No one can explain any clearer that this!!! thank you
The best explanation of this concept , Last Un-Closed , First Un-Closed , makes it clear why a stack must be used. This detail has been left out it most explanations. Great work. @9:27
Your classes are all fantastic. Thanks so much!!!
your classes are very interactive as programming perspective. I could say this is the best data structure tutorial till now we have in web.
I've learned more abuout data structures from your videos, than I have from school. Thank you.
Words are short to express my gratitude. I am able to code it in C# with your advised alsogrithm, it works in all conditions. Thank you once again.
You're a bloody genius... Thanks!
You make it sooo easy to understand. Thanks a lot!
So smoothly explained. Thank you!
I'm really grateful sir, I will forever remember you.
Thank you from the bottom of my heart ❤
I am really grateful to the person for this awesome compilation of Data Structures Thanks You!
Really awesome and helpful explaination. Thanks.
I cant thank you enough, so simple and clear ;)
thank you for this input method, made it way easier for me to understand
This guy is one enough to make learn coding the whole student community
hats off bro... thank you so much for this amazing series
thanks, this video helped a lot to understand the general idea of the algorithm
amazing lectures as well as brilliant voice
Thank you for this explanation. I have to do this exact problem for a job interview coming in the fall.
4 years later, how did it go lol
@@rohanbangash5827 Nailed this question on every interview. Funny enough I work for a company that did not ask this question. It's a great algorithm to help think about the benefits of a stack data structure.
You have the best way of teaching..🔥🔥🔥
Excellent marvellous extraordinary mind blowing fantastic awesome.no words to describe your work.thanks guruji
excellent video! i understand this concept much better now.
Sir your explanation is too good thanks for explaining me this topic of stack... 😃
Thanks for the help! really help me alot in my studies! !
Nicely explained!
Really helpful
thank u very much, very well explained! helped me a lot.
thank you a lot . you are a great teacher
Thank u so much! It was really helpful !
Remembering Lord Harsha ❤️
Great explanation !
Thank you. It was very helpful
Thank you , what a great contribution.
good work sir thnk u so much fr make a awesome creation of videos u r the real teacher thnks a lot sir plz upload more videos related to Tree,Graphs,Constructor,exceptional handling,file handling etc
great explanation sir...thanks a lot
Amazing explanation Thank you sir
Very clear instruction!
thanku you so much sir
you are healping us a lot
Wow u have all the thing i searching for
The best explanation.
It was really helpful !
Easy to understand teaching
Thank you this really helped! c:
excellent explanation
Nicely explained :)
Amazing Video..please upload some more videos on Interview Questions and MultiThreading and Design Pattern
Why would you use stack to 'park' the parantheses ? how is the possibility of any bracket finding a match within the 'parked' list/array ? Dosen;t the pop method give you always the topmost (last) instance ?
pseudo code rocks! Thanks!
Thanks a lot, very helpful
so clear , thanks alot
my exam is in two hours you are lifesaver
I’ve been asked this question in coding interview.
Great video sir
great job sir....
Nice explanation👍👍
Wow, exactly the same as what I did in an Amazon phone interview. I forgot to check s.isEmpty while peeking the stack until it threw exception in one testing, but after adding it back, it is exactly the same as what it shows here. Cool!
did you get the job tho?
@@nikunjchapagain5654 yes he was refrenced by me !!
Many many thanks,keep it up
Thank you so much Sir!
It was Helpful :)
using a stack seems a bit excessive to me, since for each character to match it must make a call to the C ++ library and this consumes cpu and memory, you can simply use a byte array of fixed length, as large as the number of characters or symbols to compare, in which in each element you can save a number corresponding to the character to be balanced, e.g. 1 corresponds to square brackets and 2 corresponds to round brackets and a global pointer which moves to the right (g_ptr ++) to insert char x,y,z and to move to the left (g_ptr--) to compare and remove char z,y,x , (if the characters do not match or if the pointer goes below zero then there is an unbalance) a method that can also be used to keep track of the states of C directives (for example excluding everything that descends from #else (including other #if #else #endif and resuming the block at the exit of the first #endif) where it is not worth using a stack or a parser e.g. LALR
Your comment is overkill, like the whole point was to show you know as much as the presenter. The video is teaching how to use an important data structure, all your extra talk about efficiency and libraries is irrelevant. Developers seeking jobs need to know what a stack is and how to use it. Period.
Understanding limitations of data structures and their accompanying algorithms IS important, but there’s no need shoehorn that in to a basic introductory video where folks are just learning how to use the structure.
Thanks so much!
can someone tell me how to aproach this problem using recursion instead of stacks? the signature of my method should be
public boolean isBalanced(String in)
We can maintain two data structure stack and queue. stack for the opening and queue for the closing parentheses.
The we can compare these two if all the parentheses are in the order.
Hi Sir,
I think after set variable n with expression length, we can check if n is even. If it’s not, n is odd and return false (Expression will contain only brackets).
the given code in the git hub will fail for the test case when we include the space in the user input because the taking of string input will not execute after a blank space I'm still having doubt on the concepts of strings and characters of user input oriented.. i will also do silly mistakes like this code which was uploaded on git hub
How do I deal with the brackets inside the quote, or comments?
Thank you.
best explanation
superb!!
Great, thank you
thank u brother
u r legend sir
thank you 🙌
thank you so much
thank you sir!
Thank you
what's the algorithm to check that the top doesn't pair with i?
Just awesome
Happy teacher's day bro
best of data structures
Thank You
Can you solve for String Anagram and word ladder?
Much smaller code in C:
// Check for paranthesis using stack and the stack here is implemented using Linked lists
#include
#include
#include
int flag = 0;
struct Node{
int data;
struct Node *link;
};
struct Node *head;
void push(int x)
{
struct Node *nod=(struct Node*)malloc(sizeof(struct Node));
nod->data=x;
nod->link=head;
head=nod;
}
char pop()
{
char n;
struct Node *temp=head;
if(head==NULL) return;
n=temp->data;
head=head->link;
free(temp);
return n;
}
void checkforparanthesis(char *A,int x)
{
char c;
for(int i=0;i
Amazing explanation :)
Thank youuu!!!
Nice videos.
To the point and easy to understand.
Where can I get code if I want ?
Sant Gupta open "see more" below the video and click on "see source code here.
would this o(n^2) time complexity? because you have for loop and inside you append items which take O(n)?
Append, Pop, Top, IsEmpty operations are O(1) in Stack. Even if we pop or append all the chars to stack, we would do that n times.
HELPFUL
if anyone requires the "C" code for the above program ::
#include
#include
#include
#define MAX 100
struct Node{
int data;
struct Node* next;
};
typedef struct Node node;
node* top = NULL;
// PUSH()
void Push(char c)
{
node* temp = (node*)malloc(sizeof(node));
temp->data = c;
temp->next = top;
top = temp;
}
// POP()
void Pop()
{
node* temp;
if (top == NULL)
{
return;
}
temp = top;
top = top->next;
free(temp);
}
int isMatching(char c){
if ( top->data == '(' && c == ')' ){
return 1;
}
else if ( top->data == '[' && c == ']' ){
return 1;
}
else if ( top->data == '{' && c == '}' ){
return 1;
}
else
return 0;
}
void isBalanced(char exp[], unsigned long len){
for (int i = 0; i
TQ so much !!!!
What does POP () function do
you r the god of data structures!!! thanks a lot! BTW where are u from in India??
It definitely seems like it. Indians are generally very good at programming anyways.
Liam he's from India and he died in 2015
Sid He died in 2015? You mean him or the person he founded My Code School with, Harsha Suryanarayana? He's the one who unfortunately passed away in 2014 or so right? This person is Animesh Nayan and he is pretty much alive?
Amrita Basu i was talking abt Harsha
Sid So Harsha created these videos ? I was under the impression that it was Animesh.
thanks
what would the Big0 of this be?
thanks bro
What is the Code ??
awesome
NICE really
thanks!
best one