ATM
Hopcroft & Ullman's TM for {0^n 1^n : n >= 0}
0 1	// input alphabet, note such comments are permitted at the end of the line
0 1 X Y B // tape alphabet
1	// number of tapes
1	// number of tracks on tape 0
1	// tape 0 is 1-way infinite
q0	// the initial state
q4      // final state(s)
q0  B  q4  B  r  // the transitions do not use "+" since there is only one track
q0  0  q1  X  r
q0  Y  q3  Y  r
q1  0  q1  0  r
q1  1  q2  Y  l
q1  Y  q1  Y  r
q2  0  q2  0  l
q2  X  q0  X  r
q2  Y  q2  Y  l
q3  Y  q3  Y  r
q3  B  q4  B  r
end 	//required