# Check if given number can be represented as sum of two great numbers

We are given a number N. We need to check if the given number N can be represented as sum of two **Great **numbers. If yes then print those two great numbers else print no. Great numbers are those which are represented in the form : ((b)*(b+1)*(2*b+1))/6 where b is a natural number.

Examples:

Input : N = 35 Output : 5 and 30 Input : 105 Output : 14 and 91 Input : 99 Output : No the given number is not a sum of two great numbers

As we know ((b)*(b+1)*(2*b+1))/6 where b is a natural number represents the sum of square of first b natural numbers. For example if b = 3 then 1+4+9 = 14. So to check if the input number n can be represented as sum of two great numbers then we will first compute all the great numbers less than n in an array. Then we will use two pointer approach to find the pair than can sum up to the given number n.

To compute the array of all the great numbers we will iterate over i=0 to i

Time Complexity: O(N)

Auxiliary Space : O(N)

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