You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
25 lines
682 B
TypeScript
25 lines
682 B
TypeScript
/**
|
|
* evaluate the difficulty of hex32 according to nip-13.
|
|
* @param hex32 a string of 64 chars - 32 bytes in hex representation
|
|
*/
|
|
export const zeroLeadingBitsCount = (hex32: string) => {
|
|
let count = 0;
|
|
for (let i = 0; i < 64; i += 2) {
|
|
const hexbyte = hex32.slice(i, i + 2); // grab next byte
|
|
if (hexbyte === '00') {
|
|
count += 8;
|
|
continue;
|
|
}
|
|
// reached non-zero byte; count number of 0 bits in hexbyte
|
|
const bits = parseInt(hexbyte, 16).toString(2).padStart(8, '0');
|
|
for (let b = 0; b < 8; b++) {
|
|
if (bits[b] === '1' ) {
|
|
break; // reached non-zero bit; stop
|
|
}
|
|
count += 1;
|
|
}
|
|
break;
|
|
}
|
|
return count;
|
|
};
|