{"raw_statement":[{"iden":"problem statement","content":"You are given $N$ distinct integers $A_1, A_2, \\dots, A_N$.  \nYou will choose $K$ of them. The **score** of a choice is defined as the product of the chosen integers.  \nThere are $\\binom{N}{K}$ possible ways to choose $K$ integers.  \nFind the sum of their scores, and output the result modulo $998244353$."},{"iden":"constraints","content":"*   $1 \\leq N \\leq 2 \\times 10^5$\n*   $1 \\leq K \\leq N$\n*   $1 \\leq A_i \\leq 10^8$\n*   If $i \\neq j$, then $A_i \\neq A_j$\n*   All input values are integers"},{"iden":"input","content":"The input is given from standard input in the following format:\n\n$N$ $K$\n$A_1$ $A_2$ $\\dots$ $A_N$"},{"iden":"sample input 1","content":"3 2\n2 3 5"},{"iden":"sample output 1","content":"31\n\nThe possible ways to choose $K$ integers and their scores are:\n\n*   Choose $A_1 = 2$ and $A_2 = 3$. The score is $2 \\times 3 = 6$.\n*   Choose $A_1 = 2$ and $A_3 = 5$. The score is $2 \\times 5 = 10$.\n*   Choose $A_2 = 3$ and $A_3 = 5$. The score is $3 \\times 5 = 15$."},{"iden":"sample input 2","content":"10 5\n1 2 3 4 5 6 7 8 9 10"},{"iden":"sample output 2","content":"902055"}],"translated_statement":null,"sample_group":[],"show_order":["default"],"formal_statement":null,"simple_statement":null,"has_page_source":true}