array-rotation-to-left-by-given-distance-d

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Array left rotation by a given number d

Step 1: Take two pointers
  1. i = 0
  2. j = arr[length]
Step 2:
 1. Swap index of all elements from i to d.
 2. Swap index of all elements from d+1 to arr[length].
Step 3:
 Swap index of all elements from i to arr[length].