Is there a length-preserving encryption scheme, that preserves the lengths of input sizes such that the length of the input plain text is same as length of the output cipher text ?
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One could design length (and format) preserving encryption schemes using Luby Rackoff Constructions (which are based on Feistel Networks)
While there are variety of variants to achieve (especially , the FFX modes of encryption ) one more notable work is done by Naor and Reigold . They introduce another layer to classic Feistel networks by using Pair-wise Independent Functions ( PWIP), which they prove to be more secure than classic version.
We have very recently re-designed their work and proposed a new, FNR mode of encryption  which is practical arbitrary length block cipher algorithm to do the same . One could build format-preserving-encryption using such scheme. Which is variant of Naor and Reingold's work .
 Naor, Moni, and Omer Reingold. "On the Construction of Pseudorandom Permutations: Luby—Rackoff Revisited." Journal of Cryptology 12.1 (1999): 29-66.
Your are looking for a encryption scheme that supports length preserving encryption. I recommend to use an authenticated encryption scheme like OCB or McOE. There are two common techniques to achieve this goal:
Note that you need at least either a nonce or authentication tag -- or better both -- to preserve data privacy, i.e., security against chosen plaintext attacks (CPA).
Maybe I got you wrong. Maybe you are looking for format-preserving encryption or something else. Hence, a more detailed problem description would be great.