[Community Puzzle] Robot show

Puzzles
#89

Every robot can be facing either direction.
So it is kind of finding a best combination of directions to lead to the longest performance time.
Very Hard indeed (appears to be)…

#90

Ohhhh!, now I get it, Thanks

#91

None of the advice is helpful here as I have 100% to the test cases but only 50% to the validator. This puzzle makes no sense and I already thought about it for a while but still nothing. Not funny at all

#92

I have no idea, pls help
All tests pass, but validator 2/3/5 not

Spoil 
fn main() {
    // lenght
    let mut input_line = String::new();
    io::stdin().read_line(&mut input_line).unwrap();
    let l = parse_input!(input_line, i32);
    
    // number robot
    let mut input_line = String::new();
    io::stdin().read_line(&mut input_line).unwrap();
    let n = parse_input!(input_line, i32);
    let mut robot_begins_end = false;
    
    // position robots
    let mut inputs = String::new();
    io::stdin().read_line(&mut inputs).unwrap();
    let mut smallest_int = -1;

    for i in inputs.split_whitespace() {
        let b = parse_input!(i, i32);
        if smallest_int == -1 || b < smallest_int { smallest_int = b; }
        if b == l { robot_begins_end = true; }
    }

    if robot_begins_end {println!("{}", l); }
    else { println!("{}", l - smallest_int); }
}
#93

Feels like there is an extra step missing about “How to position bots initially”.
Works well if they start pointing to the middle of the tunnel

#94

Think simple. Think of the solution where there is only one bot. Then think of the solution where there are two bots. Think about what differences (if any) it makes when they meet and move on again.

#95

have you found the solution for the validators?
although i need to mention i have problem with validatiors 2/4/5.