how can get original value from hash value? -


my original text : "sanjay" sha-1 text : "25ecbcb559d14a98e4665d6830ac5c99991d7c25"

now how can original value - "sanjay" hash value ?

is there code or algorithm or method?

no. that's point -- process of hashing one-way.

this important hashes designed passwords or cryptology -- differ hashes designed, say, hash-maps. also, unbounded input length, there infinite amount of values result in same hash.

one method can used hash bunch of values (e.g. brute-force aaaaaaaa-zzzzzzz) , see value has same hash. if have found this, have found "the value" (the time not cheap). "rainbow tables" work on idea (but use space instead of time), defeated nonce salt.


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