I was searching the explanation of lazy propogation and I find this ->
To mark only 5…15 as “yes”, below is all you need. Only 7 nodes are involved in the operation, much less than what if you don’t use lazy propagation. It can be proved that at most 2logn - 1 nodes may be involved, where n is the range.
0..31u / \ 0..15u 16..31n / \ 0..8u 9..15y / \ 0..4n 5..8y (u: unknown, look deeper; y: yes; n: no)
We updated the node of range 9…15 bcoz it completely falls inside the range 5…15 .
Suppose if no further query comes for the range 9…15 , than how will be update each of the child node of the parent node (9…15) …??