{"raw_statement":[{"iden":"problem statement","content":"We have $N$ cards arranged in a row from left to right. We will write an integer between $1$ and $K$ (inclusive) on each of these cards, which are initially blank.\nGiven are $K$ restrictions numbered $1$ through $K$. Restriction $i$ is composed of a character $c_i$ and an integer $k_i$. If $c_i$ is `L`, the $k_i$\\-th card from the left in the row must be the **leftmost** card on which we write $i$. If $c_i$ is `R`, the $k_i$\\-th card from the left in the row must be the **rightmost** card on which we write $i$.\nNote that for each integer $i$ from $1$ through $K$, there must be at least one card on which we write $i$.\nFind the number of ways to write integers on the cards under the $K$ restrictions, modulo $998244353$."},{"iden":"constraints","content":"*   $1 \\leq N,K \\leq 1000$\n*   $c_i$ is `L` or `R`.\n*   $1 \\leq k_i \\leq N$\n*   $k_i \\neq k_j$ if $i \\neq j$."},{"iden":"input","content":"Input is given from Standard Input in the following format:\n\n$N$ $K$\n$c_1$ $k_1$\n$\\vdots$\n$c_K$ $k_K$"},{"iden":"sample input 1","content":"3 2\nL 1\nR 2"},{"iden":"sample output 1","content":"1\n\n*   The only way to meet the two restrictions is to write $1, 2, 1$ from left to right on the three cards."},{"iden":"sample input 2","content":"30 10\nR 6\nR 8\nR 7\nR 25\nL 26\nL 13\nR 14\nL 11\nL 23\nR 30"},{"iden":"sample output 2","content":"343921442\n\n*   Be sure to find the count modulo $998244353$."}],"translated_statement":null,"sample_group":[],"show_order":["default"],"formal_statement":null,"simple_statement":null,"has_page_source":true}