Ethereum wallet private key generation address
How are bitcoin addresses and private keys generated? Bitcoin uses elliptic curve algorithm to generate public key and private key, and chooses secp256k1 curve. The generated public key is a 33 byte large number, and the private key is a 32 byte large number. The wallet file wallet.dat directly stores the public key and private key. The bitcoin address we use when receiving and sending bitcoin is obtained after the public key is processed by the algorithm. The specific process is that the public key is first processed by SHA-256 algorithm to get 32 byte hash result, then processed by ripemed algorithm to get 20 byte summary result, and then the address we see is obtained through the character conversion process. This character conversion process is the same as that of the private key. The steps are as follows: first, add the version number to the input content (the summary result of 20 bytes for the public key and the large number of 32 bytes for the private key). After two successive SHA-256 algorithms, take the first 4 bytes of the hash result of the last time as the check code and attach it to the back of the input content, and then encode it with base58, Get the string{ RRRRR}
First of all, you should imagine a concept of "wallet" in your brain. Your bitcoin is in your wallet. A wallet can contain many... Many addresses. The form of the address is the form
with the bitcoin address generated in the bitcoin wallet, you can receive bitcoin from others, and you can also transfer the bitcoin in your account to the bitcoin address of others. Bitcoin address, like bank card number, has the functions of payment, transfer and withdrawal. However, when transferring money, you can only transfer money by knowing someone else's bitcoin address
if we simply compare a bitcoin wallet to a bank card account, then the address of the bitcoin wallet can be regarded as a bank card account number. The difference is that bitcoin addresses can not be stored on the network, but also exist independently of your wallet
bitcoin address is a string of 26 to 34 letters and numbers. It looks like a lot of messy code. To put it bluntly, it's just like your bank card number. All transfer records of each bitcoin address can be checked through blockchain query, which is open and transparent
address generation of bitcoin Wallet: 256 binary digits are randomly selected to form the private key, and then the address is generated by encryption function. This generation direction is unidirectional. That is, you know that the address cannot be decrypted to calculate the private key. At present, the computing power of human computer can't be cracked, so you can publish the address on the Internet with ease
reference link: bitcoin | network
first of all, confinement is usually for one month. So whether at home or in the confinement center is the same, it needs to live for a month. But this time is not certain, can only be said to be at least a month's time to live. A month is a minimum time, even if the maternal recovery is fast, but also to live enough for a month. But if the maternal recovery is relatively slow, then it is not only to live for a month, it is necessary to live longer. Therefore, it is more recommended that pregnant women take delivery at home, which is more convenient and comfortable<
secondly, confinement is the key period for a newborn baby to recover. During this period, it is necessary to take good care of the baby. The time of each confinement is different, but it is generally 30 days or 42 days, so the body will recover more completely
in the end, the place to take delivery of the baby must choose a better place, a place with more complete facilities and better service. Otherwise, if the pregnant woman goes to the delivery center and no one is in charge, the delivery of the baby will be greatly reced
pay attention to diet after childbirth:
women have higher requirements for diet when they are in confinement, and many women think that there are not so many restrictions after childbirth, but as long as women are still in lactation, there are still many things to pay attention to
1. During lactation, women should not eat food with milk returning function, such as leek, malt, etc. Many women think ginseng tonic body is very effective, but ginseng will make maternal milk, in breast-feeding, it is best not to eat. In addition, more estrogen content of food is also easy to cause milk, such as pigeons, hens and so on
2. Women should not eat caffeinated food ring lactation. Caffeine can stimulate the nervous system. It is likely to enter the child's body through milk, causing damage to the child's nervous system and heart, and also causing indigestion
3. Eat less salt and monosodium glutamate, too much salt will increase the burden on the kidney. And monosodium glutamate will affect the development of children, eat too much monosodium glutamate will make children appear mental retardation, growth retardation and so on
women should not only pay attention to their diet when they are in confinement, even when they are out of confinement, as long as they are still in the lactation period, they can not do whatever they want in their diet, so as not to have adverse effects on their children.
This question is very strange. I recommend you to see the introction of professional media
Through the method of experiment, the cutting force data of various influencing factors are measured, and the expression reflecting the relationship between various factors and cutting force is obtained by processing, which is called the empirical formula of cutting force calculation
In practice, there are two empirical formulas of cutting force: one is exponential formula, the other is unit cutting force. Exponential formula: FC = KC & # 8226; ap• f=kc• hd• bd kc=Fc/A d=Fc/(a p• f)=F c/(b d• h d)FP -- back force (n)
Ff -- awesome force (N). p>
extended data:
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