Can anyone suggest a good algo for this question

#1
#2

A problem to use simple divisibility rules.

Take the cumulative sum of the array. For a particular index, subtract that number and then check if the remaining sum is divisible by 3 or not.

Take the previous value a[i-1] and the last value a[n] for checking the divisibility by 2 and 5.

For queries: For a particular index, store how many lucky indices are there before that index. Then for given L and R the answer would be answer[R] - answer[L-1] .

#3

Sir the code is showing TLE error in most of the test cases can you check the code.

#4

@mukuuu
You need to take cumulative sum
You’re running a loop instead
Shift to cumulative sum approach
For reference https://www.geeksforgeeks.org/cpp-program-for-range-sum-queries-without-updates/

#5

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