Input : A set S of planar points Output : A convex hull for S Step 1: If S contains no more than f

Input : A set S of planar points Output : A convex hull for S Step 1: If S contains no more than five points, use exhaustive searching to find the convex hull and return. Step 2: Find a median line perpendicular to the X-axis which divides S into SL and SR SL lies to the left of SR . Step 3: Recursively construct convex hulls for SL and SR. Denote these convex hulls by Hull(SL) and Hull(SR) respectively. Step 4: Apply the merging procedure to merge Hull(SL) and Hull(SR) together to form a convex hull. Time complexity: T(n) = 2T(n/2) + O(n) = O(n log n)