Divide and Conquer
Problems on divide and conquer, including splitting an array in halves and combining the answers, counting inversions with merge sort, closest pair of points, recursive patterns and fractals, and fast exponentiation.
The recursion and sorting articles in the Basics section cover the building blocks. Related problem sets are under Sorting and Dynamic programming optimization.
Problems
Tanglegram#222
Medium
Cake Division#1511
Very easy
Pre, in and post#1513
Medium
Gray codes#1519
Easy
Divisors#2186
Easy
Symmetry#2588
Very easy
Bicolored Horses#3248
Very hard
Worst Locations#3325
Very easy
Halloween treats#3840
Very easy
Irreducible Polynomials High#4561
Very easy
Number of requests#4652
Very hard
Divide the apples - 1#4716
Very easy
Is it divisible by 3, 6 and 9?#4734
Very easy
n Div Tree#5067
Easy
Even more fun#5488
Very hard