2016 Update

Task/Sorting-algorithms-Merge-sort/Rust/sorting-algorithms-merge-sort-1.rust

@@ -0,0 +1,23 @@
+fn merge<T: Copy + PartialOrd>(x1: &[T], x2: &[T], y: &mut [T]) {
+	assert_eq!(x1.len() + x2.len(), y.len());
+	let mut i = 0;
+	let mut j = 0;
+	let mut k = 0;
+	while i < x1.len() && j < x2.len() {
+		if x1[i] < x2[j] {
+			y[k] = x1[i];
+			k += 1;
+			i += 1;
+		} else {
+			y[k] = x2[j];
+			k += 1;
+			j += 1;
+		}
+	}
+	if i < x1.len() {
+		y[k..].copy_from_slice(&x1[i..]);
+	}
+	if j < x2.len() {
+		y[k..].copy_from_slice(&x2[j..]);
+	}
+}

Task/Sorting-algorithms-Merge-sort/Rust/sorting-algorithms-merge-sort-2.rust

@@ -0,0 +1,17 @@
+fn merge_sort_rec<T: Copy + Ord>(x: &mut [T]) {
+	let n = x.len();
+	let m = n / 2;
+	
+	if n <= 1 {
+		return;
+	}
+	
+	merge_sort_rec(&mut x[0..m]);
+	merge_sort_rec(&mut x[m..n]);
+		
+	let mut y: Vec<T> = x.to_vec();
+	
+	merge(&x[0..m], &x[m..n], &mut y[..]);
+	
+	x.copy_from_slice(&y);
+}

Task/Sorting-algorithms-Merge-sort/Rust/sorting-algorithms-merge-sort-3.rust

@@ -0,0 +1,35 @@
+fn merge_sort<T: Copy + PartialOrd>(x: &mut [T]) {
+	let n = x.len();
+	let mut y = x.to_vec();
+	let mut len = 1;
+	while len < n {
+		let mut i = 0;
+		while i < n {
+			if i + len >= n {
+				y[i..].copy_from_slice(&x[i..]);
+			} else if i + 2 * len > n {
+				merge(&x[i..i+len], &x[i+len..], &mut y[i..]);				
+			} else {
+				merge(&x[i..i+len], &x[i+len..i+2*len], &mut y[i..i+2*len]);
+			}
+			i += 2 * len;
+		}
+		len *= 2;
+		if len >= n {
+			x.copy_from_slice(&y);
+			return;
+		}
+		i = 0;
+		while i < n {
+			if i + len >= n {
+				x[i..].copy_from_slice(&y[i..]);
+			} else if i + 2 * len > n {
+				merge(&y[i..i+len], &y[i+len..], &mut x[i..]);				
+			} else {
+				merge(&y[i..i+len], &y[i+len..i+2*len], &mut x[i..i+2*len]);
+			}
+			i += 2 * len;
+		}
+		len *= 2;
+	}
+}