Unexpected behaviour Bitcoin RPC getbalance

I am seeing a smaller amount of BTC when I run ./bitcoin-cli getbalance compared to ./bitcoin-cli getbalance “” Here is the documentation on GetBalance from the BTC wiki, which highlights why I am confused getbalance [account] [minconf=1] If [account] is not specified, returns the server’s total available balance. If [account] is specified, returns the balance…

Can we measure bitcoin’s accumulated work in terms of entropy (in bits) directly rather than expected number of hashes?

The Background Bitcoin tracks chain work by counting the (expected) minimum number of hashes it would take to create a chain of the same number of blocks and same difficulty steps[1]. Naturally, accumulated work measured in this fashion (e.g. expected number of hashes) increases with each new block that is added to the chain. For…

Solidity. Find whether a key exists in a mapping. Then get its value

I have a simple mapping: mapping(address => string) professorsExam; How can I check if msg.sender is a key in this mapping, and if it is, get its value? If it isn’t I should return something. string memory professorsExamHash = professorsExam[msg.sender]; // The hash of the exam owned by msg.sender if(professorsExamHash == 0x0){ return “No exam…

Sent BTC from Coinbase, blockchain explorer says Confirmed. Is recipient lying or could something else be the issue?

Sent BTC (approx $500) from Coinbase, Blockchain explorer says Confirmed. Is recipient lying they have not received or could something else be the issue such as his wallet? Recipient says it could be because his ‘hard’ wallet is set up in a way so it activates/acknowledges/receives with $1000 transaction minimum? He is meant to send…

How to use delegate call with or without arguments functions?

Below is my contract: contract A{ mapping (address => uint) public balances; function put() payable public { balances[msg.sender] = msg.value; } function get(address lucky) public { require(msg.sender != lucky); if (!lucky.call.value(balances[msg.sender])()) { revert(); } balances[msg.sender] = 0; } function() payable public {} } Now, I need to invoke the get function and the put function…