#P10670. Summation Modulo
Summation Modulo
Summation Modulo
Compute the following sum modulo \(998244353\):
\[ S = \sum_{n=1}^{N} \sum_{m=1}^{M} \sum_{k=0}^{m-1} \left\lfloor \frac{nk+x}{m} \right\rfloor \]
Here, \(x\) is a real number and \(N, M\) are positive integers. The symbol \(\lfloor y \rfloor\) denotes the greatest integer less than or equal to \(y\).
inputFormat
The input consists of three values separated by spaces: an integer (N), an integer (M), and a real number (x).
outputFormat
Output a single integer: the value of the sum modulo (998244353).
sample
1 1 5
5