P8249 Mod Problem.

A simple problem with no background.

You have two positive integers $a,b$. You also have a positive integer $q$, and you need to process $q$ queries. For each query, you are given two positive integers $l,r$. You need to find $\max\{(i \bmod a)+(i \bmod b)\}$, where $i$ is a positive integer and $i \in [l,r]$.

The first line contains two positive integers $a,b$. The second line contains one positive integer $q$. The next $q$ lines each contain two positive integers $l,r$.

For each query, output one line containing one integer, which is the answer.

For $30\%$ of the testdata, $1 \le q \le 10^3$ and $1 \le l \le r \le 10^3$. For $70\%$ of the testdata, $1 \le q \le 10^3$ and $1 \le l \le r \le 10^9$. For $100\%$ of the testdata, $1 \le a,b \le 10^3$, $1 \le q \le 10^5$, and $1 \le l \le r \le 10^9$. Translated by ChatGPT 5