human
Count frequencies of all elements in array in O ( 1 ) extra space and O ( n ) time | Function to find counts of all elements present in arr [ 0. . n - 1 ] . The array elements must be range from 1 to n.
Subtract 1 from every element so that the elements become in range from 0 to n - 1.
Use every element arr [ i ] as index and add ' n ' to element present at arr [ i ] % n to keep track of count of occurrences of arr [ i ].
To print counts , simply print the number of times n was added at index corresponding to every element.
Driver code"
How can the above be solved in Python?

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Can you provide a code to count frequencies of all elements in array in O ( 1 ) extra space and O ( n ) time and the other steps required?
assistant
#Here is code to count frequencies of all elements in array in O ( 1 ) extra space and O ( n ) time and the other steps required.
 def printfrequency ( arr , n ) :
	for j in range ( n ) :
		arr [ j ] = arr [ j ] - 1
	for i in range ( n ) :
		arr [ arr [ i ] % n ] = arr [ arr [ i ] % n ] + n
	for i in range ( n ) :
		print ( i + 1 , " - > " , arr [ i ] // n )
arr = [ 2 , 3 , 3 , 2 , 5 ]
n = len ( arr )
printfrequency ( arr , n )