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BuyMyMojo 2022-03-06 17:33:35 +11:00
parent 21a62f9125
commit 91bd5533e4
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2 changed files with 28 additions and 5 deletions
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@ -1,5 +1,11 @@
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27
src/main.rs
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@ -74,7 +74,10 @@ fn txpo(mut current_num: u128) -> (u128, u128) {
largest_num = current_num;
}
current_num = current_num.mul(3) + 1; // For some reason using .mul() is faster then * but .add() is slightly slower then +. it was only a few ms slower to do all 50K but on an extremely large scale it matters
// For some reason using .mul() is faster then * but .add() is slightly slower then +.
// it was only a few ms slower to do all 50K but on an extremely large scale it matters.
current_num = current_num.mul(3) + 1;
} else {
if current_num < smallest_num{
smallest_num = current_num;
@ -84,7 +87,22 @@ fn txpo(mut current_num: u128) -> (u128, u128) {
largest_num = current_num;
}
current_num = current_num >> 1; // Divides by 2 a bit faster
// Writing this one line taught me about bit shifting.
// doing >> on an unsigned integer (u8-u16-u32-u64-u128) does something called
// Logical Right Shifting. This removes the least significant bit or the right most
// bit and places a 0 on the left. so the binary form of 8 is 1000, doing 8>>1 shifts
// the bits to the right once, this takes the last 0 and removes it making it 100, we
// then add a new 0 to the left making it 0100 which is binary for 4.
// This is more efficient then just trying to do division because there is no actual
// math involved and just a super quick bit operation.
//
// Another example:
// 69420 >> 1 == 34710
// 0001 0000 1111 0010 1100 >> 1
// 0001 0000 1111 0010 110
// 0000 1000 0111 1001 0110 == 34710
//
current_num = current_num >> 1;
}
if current_num == smallest_num {
@ -107,7 +125,6 @@ fn verbose_txpo(mut current_num: u128) -> (u128, u128) {
let mut smallest_num_count = 1;
while smallest_num_count != 2{
// if odd
if current_num % 2 != 0 {
if current_num < smallest_num{
smallest_num = current_num;
@ -119,7 +136,7 @@ fn verbose_txpo(mut current_num: u128) -> (u128, u128) {
event!(Level::INFO, "{} is odd. Smallest number: {}. Largest number: {}", current_num, smallest_num, largest_num);
current_num = current_num.mul(3) + 1; // For some reason using .mul() is faster then * but .add() is slightly slower then +. it was only a few ms slower to do all 50K but on an extremely large scale it matters
current_num = current_num.mul(3) + 1;
} else {
if current_num < smallest_num{
smallest_num = current_num;
@ -131,7 +148,7 @@ fn verbose_txpo(mut current_num: u128) -> (u128, u128) {
event!(Level::INFO, "{} is even. Smallest number: {}. Largest number: {}", current_num, smallest_num, largest_num);
current_num = current_num >> 1; // Divides by 2 a bit faster
current_num = current_num >> 1;
}
if current_num == smallest_num {