Suppose you are given an array s[1....n] and a procedure

Suppose you are given an array s[1....n] and a procedure reverse (s,i,j) which reverses the order of elements in a between positions i and j (both inclusive). What does the following sequence do, where 1 ≤ k ≤ n :
reverse (s, 1, k);
reverse (s, k + 1, n);
reverse (s, 1, n);

1. Rotates s left by k positions
2. Leaves s unchanged
3. Reverses all elements of s
4. None of these

From the given conditions it can be clearly concluded that, the given sequence rotates s left by k positions.