atcoder#ARC082D. [ARC082F] Sandglass
[ARC082F] Sandglass
Score : points
Problem Statement
We have a sandglass consisting of two bulbs, bulb A and bulb B. These bulbs contain some amount of sand. When we put the sandglass, either bulb or lies on top of the other and becomes the upper bulb. The other bulb becomes the lower bulb.
The sand drops from the upper bulb to the lower bulb at a rate of gram per second. When the upper bulb no longer contains any sand, nothing happens.
Initially at time , bulb A is the upper bulb and contains grams of sand; bulb B contains grams of sand (for a total of grams).
We will turn over the sandglass at time . Assume that this is an instantaneous action and takes no time. Here, time refer to the time seconds after time .
You are given queries. Each query is in the form of . For each query, assume that and find the amount of sand that would be contained in bulb A at time .
Constraints
- $1 \leq r_1
- $0 \leq t_1
- All input values are integers.
Input
The input is given from Standard Input in the following format:
..
Output
For each query, print the answer in its own line.
180
3
60 120 180
3
30 90
61 1
180 180
60
1
120
In the first query, out of the initial grams of sand will drop from bulb A, resulting in grams. In the second query, the initial gram of sand will drop from bulb A, and nothing will happen for the next seconds. Then, we will turn over the sandglass, and second after this, bulb contains gram of sand at the time in question.
100
1
100000
4
0 100
90 100
100 100
101 100
100
10
0
0
In every query, the upper bulb initially contains grams, and the question in time comes before we turn over the sandglass.
100
5
48 141 231 314 425
7
0 19
50 98
143 30
231 55
342 0
365 100
600 10
19
52
91
10
58
42
100