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@@ -1,38 +0,0 @@
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-pragma solidity ^0.4.4;
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-
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-
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-/*
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- * Proof of Existence example contract
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- * see https://medium.com/zeppelin-blog/the-hitchhikers-guide-to-smart-contracts-in-ethereum-848f08001f05
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- */
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-contract ProofOfExistence {
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-
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- mapping (bytes32 => bool) public proofs;
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-
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- // store a proof of existence in the contract state
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- function storeProof(bytes32 proof) {
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- proofs[proof] = true;
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- }
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-
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- // calculate and store the proof for a document
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- function notarize(string document) {
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- var proof = calculateProof(document);
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- storeProof(proof);
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- }
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-
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- // helper function to get a document's sha256
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- function calculateProof(string document) constant returns (bytes32) {
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- return sha256(document);
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- }
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-
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- // check if a document has been notarized
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- function checkDocument(string document) constant returns (bool) {
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- var proof = calculateProof(document);
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- return hasProof(proof);
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- }
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-
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- // returns true if proof is stored
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- function hasProof(bytes32 proof) constant returns (bool) {
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- return proofs[proof];
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- }
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-}
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