2D prefix sum - MarisaOJ: Marisa Online Judge

2D prefix sum

Time limit: 1000 ms
Memory limit: 256 MB
You are given a 2D integer array $A$ of size $n \times m$ and $q$ queries of form $(a, b, c, d)$, calculate the sum of the subarray with upper-left corner $(a, b)$ and lower-right corner $(c, d)$. ### Input - The first line contains 3 integers $n, m, q$. - Each line in the next $n$ lines contains $m$ integers $A_{i, j}$. - Each line in the next $q$ lines contains 4 integers $a, b, c, d$. ### Output - Print $q$ line, $i^{th}$ line is the answer for query $i$. ### Constraints - $1 \le n, m \le 1000$. - $1 \le q \le 10^5$ - $1 \le A_i \le 10^9$. ### Example Input: ``` 2 3 2 1 4 3 2 2 3 1 1 2 2 2 1 2 3 ``` Output: ``` 9 7 ```