The Two Train Problem

[Eddie W. Shore]

CORRECTED PROGRAM:

Code:


EXPORT TRAINS()
BEGIN
// 2018-02-22 EWS
// 2 trains problem

LOCAL d,t,x;
LOCAL v1,a1,v2,a2;

INPUT({d,v1,a1,v2,a2},
"Two Opposing Trains",
{"Dist:","L Vel:","L Acc:",
"R Vel:","R Acc:"},
{"Distance between trains",
"Left Train: Velocity",
"Left Train: Acceleration",
"Right Train: Velocity",
"Right Train: Acceleration"});

// calculation
IF a1≠0 OR a2≠0 THEN
t:=(−(v1+v2)+√((v1+v2)^2+
2*d*(a1+a2)))/(a1+a2);
x:=v1*t+a1*t^2;
ELSE
t:=d/(v1+v2);
x:=v1*t;
END;

// results
RETURN {"Time",t,
"Position",x};


END;