Those who know - MarisaOJ: Marisa Online Judge

Those who know

Time limit: 500 ms
Memory limit: 256 MB
Alice challenged Patchouli a game to determine her knowledge about her dolls. Specifically, she created a matrix, which is a directed acyclic graph with $n$ vertices and $m$ edges. Each edge is weighed a lower-case English letter. Initially, Alice gave herself and Patchouli each a doll, onto which the letter `a` was labeled, and placed each of them on a vertex of the matrix. Each turn's event is as the following: - Each person can move their doll from vertex $u$ to vertex $v$ if and only if there exists an edge from $u$ and $v$ with a weight (letter) being **no less than** the current label alphabetically, and that very letter will be assigned to both dolls. - The first person unable to do this loses the game. Afraid that her game wouldn't be challenging enough for Patchouli (as she's one of **those who know**), Alice gave Patchouli the riddle: If both of them played optimally and Alice goes first, then for each scenario, assuming Alice's doll started at $i$, and Patchouli's doll at $j$, who would win the game? Let's help Patchouli find the answer! ### Input: The first lines contains $2$ integers $n$ and $m$ - The number of vertices and edges of the matrix. The next $m$ lines, each consists of $2$ integers $u$ and $v$, and a letter $w$ - Indicating that there exists an edge from $u$ to $v$, to which $w$ was assigned. ### Output: Print a $n \times n$ matrix of characters, `A` at row $i$, column $j$, if Alice would win the game if her doll was placed on vertex $i$, Patchouli's on vertex $j$, and `P` otherwise. ### Constraints - $1 \le n \le 100$. - $1 \le m \le \frac{ n \times (n - 1)}2$. - $1 \leq u, v \leq n$. It is guaranteed that the matrix is a directed acyclic graph, and that there should exist no pair of vertices connected by more than $1$ edge. ### Example Input: ``` 4 4 1 2 h 2 4 a 2 3 w 3 4 k ``` Output: ``` PAAA APAA APPA PPPP ```
Topic
Dynamic Programming
Rating 1700
Source Codeforces
Solution (0) Solution