A12994. Changing Volume

Bob watches TV every day. He always sets the volume of his TV to $b$ . However, today he is angry to find out someone has changed the volume to $a$ . Of course, Bob has a remote control that can change the volume.

There are six buttons ( $-5, -2, -1, +1, +2, +5$ ) on the control, which in one press can either increase or decrease the current volume by $1$ , $2$ , or $5$ . The volume can be arbitrarily large, but can never be negative. In other words, Bob cannot press the button if it causes the volume to be lower than $0$ .

As Bob is so angry, he wants to change the volume to $b$ using as few button presses as possible. However, he forgets how to do such simple calculations, so he asks you for help. Write a program that given $a$ and $b$ , finds the minimum number of presses to change the TV volume from $a$ to $b$ .

Each test contains multiple test cases. The first line contains the number of test cases $T$ ( $1 \le T \le 1\,000$ ). Then the descriptions of the test cases follow.

Each test case consists of one line containing two integers $a$ and $b$ ( $0 \le a, b \le 10^{9}$ ) — the current volume and Bob's desired volume, respectively.

For each test case, output a single integer — the minimum number of presses to change the TV volume from $a$ to $b$ . If Bob does not need to change the volume (i.e. $a=b$ ), then print $0$ .

In the first example, Bob can press the $-2$ button twice to reach $0$ . Note that Bob can not press $-5$ when the volume is $4$ since it will make the volume negative.

In the second example, one of the optimal ways for Bob is to press the $+5$ twice, then press $-1$ once.

In the last example, Bob can press the $+5$ once, then press $+1$ .