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Check if given string is a substring of string formed by repeated concatenation of z to a | Function checks if a given is valid or not and prints the output.
Boolean flag variable to mark if given is valid.
Traverse the given string.
If adjacent character differ by 1.
If character ' a ' is followed by 4.
Else flip the flag and break from the loop.
Output according to flag variable.
Driver Code.
Given string.
Function Call"
Solution in Python:

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What is a code to check if given string is a substring of string formed by repeated concatenation of z to a and the other steps required?
assistant
#Here is code to check if given string is a substring of string formed by repeated concatenation of z to a and the other steps required.
 def checkInfinite ( s ) :
	flag = 1
	N = len ( s )
	for i in range ( N - 1 ) :
		if ( s [ i ] == chr ( ord ( s [ i + 1 ] ) + 1 ) ) :
			continue
		elif ( s [ i ] == ' a ' and s [ i + 1 ] == ' z ' ) :
			continue
		else :
			flag = 0
			break
	if ( flag == 0 ) :
		print ( " NO " )
	else :
		print ( " YES " )
if __name__ == ' _ _ main _ _ ' :
	s = " ecbaz "
	checkInfinite ( s )