new instruction rjmp

src/instructions/mod.rs

@@ -38,4 +38,5 @@ pub mod kjz;
 pub mod print;
 pub mod println;
 pub mod insert;
-pub mod random;
+pub mod random;
+pub mod rjmp;

src/instructions/rjmp.rs

@@ -0,0 +1,8 @@
+use crate::stack::StackVec;
+
+pub fn rjmp(memory: &mut StackVec, labels: &mut [Option<i16>; 256], program_counter: &mut u16) {
+    let start = memory.pop() as usize;
+    let end   = memory.pop() as usize;
+
+    *program_counter = (labels[fastrand::usize(start..end)].unwrap() - 1) as u16;
+}