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Learning Opportunities
This puzzle can be solved using the following concepts. Practice using these concepts and improve your skills.
Statement
Goal
Welcome soldier,It is in the heart of World War 2 and imagine yourself hunkered down in a trench line with your squad, and that there is also an enemy squad nearby opposing your movement. Both squads appear evenly matched, and there has been a stalemate for hours. There is a mortar kit which includes a rudimentary range finder, but unfortunately for your squad, no one knows how to operate it properly; however, at this point, attempting to use it is becoming your only viable option. You hop onto the radio with your superior who puts you through to an artillery specialist...
"Listen up, lieutenant. Do you have a pen, paper, and your slide rule? Good, you will need those to do your calculations. Your range finder is going to provide you with a horizontal distance between you and the enemy unit. The stereoscope will need to be focused for an accurate reading. I recommend that you don't get spotted using it just yet. You will then need to use that range and also the
M2 Mortar Round Specifications:
Shell Weight 1.4kg
Caliber 60mm
Elevation
Rate of Fire 18 rounds/minute
Max Range
Initial Velocity
(Source: https://en.wikipedia.org/wiki/M2_mortar)
Physics Formulas:
Θ = (arcsin((R*g)/v^2))/2
t = (2*v*sinΘ)/g
Where
R = Range (in meters)
g = Acceleration due to gravity (9.8 meters/second^2)
v = Initial velocity (in meters/second)
Θ = Mortar angle/elevation (in radians)
t = Time of Flight (in seconds)
Note that the potential trajectories come in pairs where there are two different angles that can achieve the same range. For example, if the calculation produces an elevation of 10°, then 80° (90° - 10°) will also work.
(Source: https://openstax.org/books/university-physics-volume-1/pages/4-3-projectile-motion
I derived the formula for theta, but more information is available in this free text. I recommend reading through the short section on Projectile Motion completely if you have the time, specifically the sub-section Time of Flight, Trajectory, and Range.)
In this problem, we can assume zero air resistance, and that the mortar and the target have the same vertical displacement (they are in-line horizontally).
Input
Line 1: A string which includes the range in meters. Extraneous characters represent the rangefinder being out of focus, but the digits included are the range needed for the problem.
Output
Line 1: The value of the angle rounded to the tenth of a degree.
Line 2: The time of flight rounded to the nearest tenth of a second.
If the target is out of range, simply printOUT OF RANGE .
Line 2: The time of flight rounded to the nearest tenth of a second.
If the target is out of range, simply print
Constraints
There are a couple constraints embedded in the problem statement.
Example
Input
-+500+--
Output
84.3 degrees 32.1 seconds
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