Set right-adjacent bits: Difference between revisions

Content added Content deleted

Inline

@@ Line 601: / Line 601: @@
 011111111111111011111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111110
 111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111110</pre>
+=={{header|Rust}}==
+<lang rust>use std::ops::{BitOrAssign, Shr};
+fn set_right_adjacent_bits<E: Clone + BitOrAssign + Shr<usize, Output = E>>(b: &mut E, n: usize) {
+    for _ in 1..=n {
+        *b |= b.clone() >> 1;
+    }
+}
+macro_rules! test {
+    ( $t:ident, $n:expr, $e:expr, $g:ty, $b:expr, $c:expr$(,)? ) => {
+        #[test]
+        fn $t() {
+            let n: usize = $n;
+            let e: usize = $e;
+            let b_original: $g = $b;
+            let mut b = b_original.clone();
+            set_right_adjacent_bits(&mut b, n);
+            println!("n = {n}; e = {e}:");
+            println!("          b = {:0>e$b}", b_original);
+            println!("     output = {:0>e$b}", b);
+            assert_eq!(b, $c);
+        }
+    };
+}
+test!(test_a1, 2, 4, u8, 0b1000, 0b1110);
+test!(test_a2, 2, 4, u8, 0b0100, 0b0111);
+test!(test_a3, 2, 4, u8, 0b0010, 0b0011);
+test!(test_a4, 2, 4, u8, 0b0000, 0b0000);
+test!(
+    test_b1, 0, 66, u128,
+b010000000000100000000010000000010000000100000010000010000100010010,
+b010000000000100000000010000000010000000100000010000010000100010010,
+);
+test!(
+    test_b2, 1, 66, u128,
+b010000000000100000000010000000010000000100000010000010000100010010,
+b011000000000110000000011000000011000000110000011000011000110011011,
+);
+test!(
+    test_b3, 2, 66, u128,
+b010000000000100000000010000000010000000100000010000010000100010010,
+b011100000000111000000011100000011100000111000011100011100111011111,
+);
+test!(
+    test_b4, 3, 66, u128,
+b010000000000100000000010000000010000000100000010000010000100010010,
+b011110000000111100000011110000011110000111100011110011110111111111,
+);</lang>
+{{out}}
+<pre>
+n = 2; e = 4:
+          b = 1000
+     output = 1110
+n = 2; e = 4:
+          b = 0100
+     output = 0111
+n = 2; e = 4:
+          b = 0010
+     output = 0011
+n = 2; e = 4:
+          b = 0000
+     output = 0000
+n = 0; e = 66:
+          b = 010000000000100000000010000000010000000100000010000010000100010010
+     output = 010000000000100000000010000000010000000100000010000010000100010010
+n = 1; e = 66:
+          b = 010000000000100000000010000000010000000100000010000010000100010010
+     output = 011000000000110000000011000000011000000110000011000011000110011011
+n = 2; e = 66:
+          b = 010000000000100000000010000000010000000100000010000010000100010010
+     output = 011100000000111000000011100000011100000111000011100011100111011111
+n = 3; e = 66:
+          b = 010000000000100000000010000000010000000100000010000010000100010010
+     output = 011110000000111100000011110000011110000111100011110011110111111111
+</pre>
 =={{header|Wren}}==