Root finding using the Bisection Method - the program

I discussed the logic for this program in a previous blog. Here is the logic converted into a program for the fx-50F:-

?→A:A→C:0→X:Goto 1:Lbl 2:Y→M:?→B:?→D:Lbl 4:X+1→X:.5(A+B)→C:.5(B-A)<D=>Goto 0:Goto 1:Lbl 3:Y=0=>Goto 0:If MY>0:Then C→A:Y→M:Else C→B:IfEnd:Goto 4:Lbl 0:C▲X▲Lbl 1:C-COS(C)→Y:X=0=>Goto 2:X≠0=>Goto 3:

This is pretty much how the program looks when keyed into the calculator in edit mode. Special Program Commands (? → => : Lbl = < > ≠ If Then Else IfEnd ▲ Goto) are input using the [SHIFT] [P-CMD] keys. The cursor key (marked Replay) is used to switch between various screens of commands. Memory variables A, B, C, D, X, Y, and M are input using [ALPHA] [A], [B] etc keys. The ":" Separator Code command is used frequently and can be alternatively input using the [EXE] key.

This program is 132 steps in length.