More bitmagic. Theme update

content/post/bit-magic/index.md

@@ -10,7 +10,7 @@ categories: []
 date: 2020-06-13T19:01:19+02:00
 lastmod: 2020-06-13T19:01:19+02:00
 featured: false
-draft: true
+draft: false
 
 # Featured image
 # To use, add an image named `featured.jpg/png` to your page's folder.
@@ -58,3 +58,30 @@ variable ^= (1 << bit);
 // Multiple bits
 variable ^= (0b101 << bit);
 ```
+
+# Math
+```c
+// Division using bitshift
+output = input >> 1; // Divide by 2
+output = input >> 2; // Divide by 4
+output = input >> 3; // Divide by 8
+// Multiply using bitshifting
+output = input << 1; // Multiply by 2
+output = input << 2; // Multiply by 4
+output = input << 3; // Multiply by 8
+```
+
+# Set X number of bits high.
+```c
+output = (0b1 << X) -1;
+```
+
+# Miccelean
+```c
+// Check if number is ODD
+if( (num & 1) == 1) {};
+// Flip signed integer
+num = ~num + 1;
+// Power of two
+num > 0 && (num & (num - 1)) == 0;
+```