Find Matching pairs of numbers

Question

How could code be written to output a number for every two numbers that are identical? For example given 223323436577 would print out 2 3 7.

Answer 1

'''With 2 numbers that are identical I assume you mean 2 characters that are next to each other that are the same
In that case, try this in Python.'''

'''Find Matching pairs of numbers

How could code be written to output a number for every two numbers that are identical? For example given 223323436577 would print out 2 3 7.'''

inp='223323436577'

print(*[inp[i] for i in range(len(inp)-1) if(inp[i]==inp[i+1])])

Answer 2

You have not mentioned the language but in python its very simple,
l=set(map(int,list(input())))
for i in l:
print(i,end=' ')
Here we have split the input and the set converts all the same type of digits into a single value or in short deletes all duplicate values from the input.

Answer 3

The best way, in my opinion, would be to convert whatever it is into a String, then run it through a Regular Expression Comparison.
Find recurring numbers, assign them to an array then print the result.
For a step-interval of 2 if looping through, use your language's equivalent of the 'continue' statement to repeat without execution.