Segment Trees : Build function

#1

I have implemented the code for build function in segment tree, but not getting desired output. Can u Pls tell what can be the probable reason ?
IDE : https://ide.codingblocks.com/s/197429

#2
#3

But what was the error in my code ?

#4

@aman_ishan,

  • Line 21: build(a, mid+1, e, 2*index);

It should be : build(a, mid+1, e, 2*index+1);
You have to build the left and the right subtree.

#5

return type of the buid should be int
else the min function would be calculating garbage value

line 25 2 * index+1 and 2 * index+2 was not mentioned
in main function start printing from 0 index and not 1

#6

Got that. Thank you.

#7

Also my query function is not giving desired output. For range 0-2 it should give ans as 1, but it’s giving -5. Can u pls rectify the error ? IDE :https://ide.codingblocks.com/s/197714

#8

line 43 there needs to be udpate

make it to
2 * index+ 1 , 2 * index + 2
instead
2index , 2 index + 1

#9

Also range_update function is not working properly. Pls check. IDE : https://ide.codingblocks.com/s/198726

#10

@aman_ishan
u need to add the different in the current and the required value

like currently node value is 5
and the update function passes 10
then just 10-5 needs to be added in each function call to the nodes that are effected by this…

refer the below code it is well commented:

#11

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