Here is the problem link:
As mentioned in the STROPR editorial, I’m calculating the coefficients by
(M+3)!/ (4! * (M-1)! ) = M*(M+1)(M+2)(M+3)/4!
So, here is my code link:
Here’s what I’m doing:
I’m going backwards from x.
Every loop, I calculate product = product * (M + extra) / (extra)
and then the total sum is stored in sums as sums = sums + Ax * product
and as the loop goes, the extra is incremented by one.
And then the output is sums % 1000000007
Subtasks 1 and 2 ran perfectly. But, it gave TLE in the 3rd subtask.
I don’t know where I’m making any mistake. I think that I’m using the least loops required to calculate the sum, but clearly I’m doing something wrong. Would someone please guide me in the right direction? Thanks, in advance.