runtime error!

ques : https://www.codechef.com/problems/ABX03

my solution : https://www.codechef.com/viewsolution/16737038

I have done it using persistence segment trees but it is giving RE for 2nd subtask. Please provide a counter case!

The main reason is:

See u are actually constructing segment tree dynamically,i.e u only make the node which are required.So if any range comes such that u haven’t made a node for it,it’ll cause RE.

I am talking about your query part.

Eg test case:
Input:

3 2

1 2 6

1 3 11

2 3 1000 1001 3 20 2 4

-4 -3 -4 14 -3 -1 -4 -2

Leave runtime error, but for some reason your code gives wrong output for this case-

Input
5 1
1 2 6
2 3 6
4 3 6
5 2 9
1 3 1 10 1 10 1 10
Your Output
6
Expected Output
12
1 Like

You could see this implementation if u want:

i have made trees for all the n nodes during dfs(as it will iterate to all the nodes)

in this case output of first will be 0 and for next the (u, v) = (-4, -3). Is it allowed?

Ooh sorry!! I didnt see ur build first function

I’ll see if i can find any error

No problem. Thanks for looking into my code!

I dont know if this will help u or not.But your ans is coming wrong due to which conditions like u<0 and v<0 arise which cause RE.

See this: https://www.codechef.com/viewsolution/16739781

1 Like

Thanks i had fixed it and it is now giving correct result : http://rextester.com/live/MSOIO73968 but still RE.

UPD : it got accepted :slight_smile: : https://www.codechef.com/viewsolution/16740827

Thanks :slight_smile:

Thank you mate !

Glad about that :slight_smile: