Given a number N, find the number of ways to represent this number as a sum of 2 or more consecutive natural numbers.
Input :15 Output :3 15 can be represented as: 1+2+3+4+5 4+5+6 7+8 Input :10 Output :1 10 can only be represented as: 1+2+3+4
The idea is to represent N as a sequence of length L+1 as:
N = a + (a+1) + (a+2) + .. + (a+L)
=> N = (L+1)*a + (L*(L+1))/2
=> a = (N- L*(L+1)/2)/(L+1)
We substitute the values of L starting from 1 till L*(L+1)/2 < N
If we get 'a' as a natural number then the solution should be counted.
The Time complexity for this program is O(N^0.5), because of the condition in the for loop.
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