Earliest Second to Mark Indices I

Given initial counts nums and a time-ordered list changeIndices where an index i can only be marked at seconds when changeIndices[s] == i (marking is checked after at most one optional decrement per second), find the earliest second by which every index can be reduced to zero and then marked. This is a scheduling/feasibility problem: decide whether the available decrements up to time t can be allocated so each index reaches zero before one of its appearances (commonly solved via binary search on time with a greedy check).