array-rotation & nge

Author: Rohit Dandnayak

src/data-structures/array/array-rotation.js

@@ -8,11 +8,35 @@ function rotateArray(arr) {
   return arr;
 }
 
+function gcd(a, b) {
+  if (a <= 0) return b;
+  let x = b - a;
+  return gcd(x, a);
+}
+
+function rotateJuggling(arr, d) {
+  let len = arr.length;
+  for (let i = 0; i < gcd(d, len); i++) {
+    let temp = arr[i];
+    let j = i;
+    while (1) {
+      let k = j + d;
+      if (k >= len) k = k - len;
+      if (k === i) break;
+      arr[j] = arr[k];
+      j = k;
+    }
+    arr[j] = temp;
+  }
+  return arr;
+}
+
 function rotateArrayBy(arr, d) {
   for (let i = 0; i < d; i++) {
     rotateArray(arr);
   }
   return arr;
 }
 
-console.log(rotLeft([1, 2, 3, 4, 5], 3));
+console.log(rotateArrayBy([1, 2, 3, 4, 5], 3));
+console.log(rotateJuggling([1, 2, 3, 4, 5], 3));

src/data-structures/stack/nge.js

@@ -0,0 +1,3 @@
+function printNGE(arr) {
+  for (let i, len = arr.length; i < len; i++) {}
+}