Order of Elimination — Solution & Editorial
Direct simulation with a list and a moving index modulo the shrinking size (an order-statistics tree does it in O(N log N) at larger scales).
Complexity: O(N2) worst case — fine at N ≤ 3000
Direct simulation with a list and a moving index modulo the shrinking size (an order-statistics tree does it in O(N log N) at larger scales).
Complexity: O(N2) worst case — fine at N ≤ 3000