Not clear with best approach part of Rainwater harvesting problem

#1

Sir I am not clear with the below lines-

Have a temporary variable that stores the same value as water. If no wall greater than or equal to the previous wall is found then quit. If previndex < size of the input array then subtract the temp variable from water, and loop from end of the input array to prev_index and find a wall greater than or equal to the previous wall (in this case, the last wall from backwards).

(Source: Rainwater harvesting problem)

#2

@akshits2022_6792a35bc37f2f39 buddy refer you’ll get everything for this question

#3

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