human
Program to build a DFA to accept strings that start and end with same character | Function for the state Q1.
Condition to check end of string.
State transitions ' a ' takes to q1 , and ' b ' takes to q2.
Function for the state Q2.
Condition to check end of string.
State transitions ' a ' takes to q1 , and ' b ' takes to q2.
Function for the state Q3.
Condition to check end of string.
State transitions ' a ' takes to q4 , and ' b ' takes to q3.
Function for the state Q4.
Condition to check end of string.
State transitions ' a ' takes to q4 , and ' b ' takes to q3.
Function for the state Q0.
Condition to check end of string.
State transitions ' a ' takes to q1 , and ' b ' takes to q3.
Driver Code.
Since q0 is the starting state Send the string to q0"
How can the above be solved in Python?

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Write me a code to program to build a DFA to accept strings that start and end with same character and the other steps required?
assistant
#Here is code to program to build a DFA to accept strings that start and end with same character and the other steps required.
 def q1 ( s , i ) :
	if ( i == len ( s ) ) :
		print ( " Yes " ) ;
		return ;
	if ( s [ i ] == ' a ' ) :
		q1 ( s , i + 1 ) ;
	else :
		q2 ( s , i + 1 ) ;
def q2 ( s , i ) :
	if ( i == len ( s ) ) :
		print ( " No " ) ;
		return ;
	if ( s [ i ] == ' a ' ) :
		q1 ( s , i + 1 ) ;
	else :
		q2 ( s , i + 1 ) ;
def q3 ( s , i ) :
	if ( i == len ( s ) ) :
		print ( " Yes " ) ;
		return ;
	if ( s [ i ] == ' a ' ) :
		q4 ( s , i + 1 ) ;
	else :
		q3 ( s , i + 1 ) ;
def q4 ( s , i ) :
	if ( i == s . length ( ) ) :
		print ( " No " ) ;
		return ;
	if ( s [ i ] == ' a ' ) :
		q4 ( s , i + 1 ) ;
	else :
		q3 ( s , i + 1 ) ;
def q0 ( s , i ) :
	if ( i == len ( s ) ) :
		print ( " No " ) ;
		return ;
	if ( s [ i ] == ' a ' ) :
		q1 ( s , i + 1 ) ;
	else :
		q3 ( s , i + 1 ) ;
if __name__ == ' _ _ main _ _ ' :
	s = " abbaabb " ;
	q0 ( s , 0 ) ;