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Дерево хешей (Merkle tree)

              PUSH1 0x60
              PUSH1 0x40
              MSTORE
              PUSH1 0x04
              CALLDATASIZE
              LT
              PUSH2 0x00cf
              JUMPI
              PUSH4 0xffffffff
              PUSH29 0x0100000000000000000000000000000000000000000000000000000000
              PUSH1 0x00
              CALLDATALOAD
            

              // Request
              curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getBalance","params":["0x407d73d8a49eeb85d32cf465507dd71d507100c1", "latest"],"id":1}'

              // Result
              {
                "id":1,
                "jsonrpc": "2.0",
                "result": "0x0234c8a3397aab58" // 158972490234375000
              }
            

              > eth.getBlock('latest')
              {
                difficulty: 639976204,
                ...
                gasLimit: 4700036,
                gasUsed: 79376,
                hash: "0xd5b3fc641f7eeacaff29d71399213db6ad2688d6944ba0d56565e82d14ad3654",
                ...
                miner: "0x00d8ae40d9a06d0e7a2877b62e32eb959afbe16d",
                ...
                number: 2751636,
                parentHash: "0xf261529f5014340fe9b78eacc770e93ed0bc5e7cd139ac2e6b1db58c5f28789e",
                ...
                timestamp: 1519951218,
                ...
                transactions: ["0xd94dfde6f6da011d65fb1d10604cc14d8ed57d6b628cd8212d68fdb0c25ee7b6"]
              }
            

              > eth.getTransaction('0xd94dfde6f6da011d65fb1d10604cc14d8ed57d6b628cd8212d68fdb0c25ee7b6')
              {
                blockHash: "0xd5b3fc641f7eeacaff29d71399213db6ad2688d6944ba0d56565e82d14ad3654",
                blockNumber: 2751636,
                from: "0xd89d82c04d66d1df48c246c4bb807334a3bff743",
                to: "0x1f072e78ae13fceaa085b75a723fbd0c31373055",
                transactionIndex: 0,
                gas: 4700000,
                gasPrice: 50000000000,
                hash: "0xd94dfde6f6da011d65fb1d10604cc14d8ed57d6b628cd8212d68fdb0c25ee7b6",
                input: "0x82ab890a00000000000000000000000000000000000000000000000000000000000b0b40",
                nonce: 9882,
                r: "0x15d42f80400eb4a574ceb2b6d1782744c247cfb94b5a848f67d4eb47f10adac2",
                s: "0x55f32de228e5f27baa956155fe0a902a1fab34db2c4e8e138d552427c2ab0d99",
                v: "0x2a",
                value: 0
              }
            

              const InputDataDecoder = require('ethereum-input-data-decoder');
              const decoder = new InputDataDecoder(`abi.json`);
              const data = '0x82ab890a00000000000000000000000000000000000000000000000000000000000b0b40'
              decoder.decodeData(data);
              
              { name: 'update', types: [ 'uint256' ], inputs: [ BN: b0b40> ] }
            

Etherscan.io FTW

              contract Hashes {
                mapping(address => string) public mails;

                function sendMail(address a, string s) public {
                  mails[a] = s;
                }

                function getMail() public view returns(string) {
                  return mails[msg.sender];
                }
              }
            

              contract Hashes {
                mapping(address => string) public mails;

                function sendMail(address a, string s) public {
                  mails[a] = s;
                }

                function getMail() public view returns(string) {
                  return mails[msg.sender];
                }
              }
            

              contract DynArray {
                string[] public texts;
                uint public counter;

                function addText(string text) public {
                    texts.push(text);
                    counter = counter + 1;
                }
              }
            

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