|| ||Code Submission Evaluation System
CSES Problem Set
Task | Statistics
CSES - Forest QueriesCSES - Forest Queries
|Time limit:||1.00 s
||Memory limit:||512 MB|
You are given an $n \times n$ grid representing the map of a forest. Each square is either empty or contains a tree. The upper-left square has coordinates $(1,1)$, and the lower-right square has coordinates $(n,n)$.
Your task is to process $q$ queries of the form: how many trees are inside a given rectangle in the forest?
The first input line has two integers $n$ and $q$: the size of the forest and the number of queries.
Then, there are $n$ lines describing the forest. Each line has $n$ characters:
is an empty square and
is a tree.
Finally, there are $q$ lines describing the queries. Each line has four integers $y_1$, $x_1$, $y_2$, $x_2$ corresponding to the corners of a rectangle.
Print the number of trees inside each rectangle.
- $1 \le n \le 1000$
- $1 \le q \le 2 \cdot 10^5$
- $1 \le y_1 \le y_2 \le n$
- $1 \le x_1 \le x_2 \le n$
2 2 3 4
3 1 3 1
1 1 2 2