Given a range L and R, the task is to find the sum of all natural numbers in range L to R.
Input: L = 2, R = 5 Output: 14 2 + 3 + 4 + 5 = 14 Input: L = 10, R = 20 Output: 165
A naive approach is to traverse from L to R and add all the elements one by one to get the sum.
An efficient approach is to use the formula for the sum of first N natural numbers. The idea of the inclusion-exclusion principle helps to solve the above problem. Find the sum of natural numbers till R and L-1 and then subtract sum(R)-sum(l-1).
Below is the implementation of the above approach:
Sum of Natural numbers from L to R is 14
- Sum of all odd natural numbers in range L and R
- Sum of range in a series of first odd then even natural numbers
- Greatest divisor which divides all natural number in range [L, R]
- Sum of first n natural numbers
- Natural Numbers
- LCM of First n Natural Numbers
- Average of first n even natural numbers
- Sum of cubes of even and odd natural numbers
- Sum of first N natural numbers which are divisible by X or Y
- Sum of fifth powers of the first n natural numbers
- Sum of first N natural numbers which are not powers of K
- Sum of first N natural numbers which are divisible by 2 and 7
- Sum of kth powers of first n natural numbers
- Repeated sum of first N natural numbers
- Sum of squares of first n natural numbers
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