2071. Maximum Number of Tasks You Can Assign

You have n tasks and m workers. Each task has a strength requirement stored in a 0-indexed integer array tasks, with the ith task requiring tasks[i] strength to complete. The strength of each worker is stored in a 0-indexed integer array workers, with the jth worker having workers[j] strength. Each worker can only be assigned to a single task and must have a strength greater than or equal to the task’s strength requirement (i.e., workers[j] >= tasks[i]).

Additionally, you have pills magical pills that will increase a worker’s strength by strength. You can decide which workers receive the magical pills, however, you may only give each worker at most one magical pill.

Given the 0-indexed integer arrays tasks and workers and the integers pills and strength, return the maximum number of tasks that can be completed.

#define all(a) begin(a), end(a)

class Solution {
public:
    int maxTaskAssign(vector<int>& t, vector<int>& w, int p, int s) {
        sort(all(w));
        sort(all(t));
        int l = 0, r = min(t.size(), w.size());
        while(l <= r) {
            int m = (l + r) >> 1, use = 0;
            multiset<int> ms(end(w) - m, end(w));
            
            for(int i = m - 1; i >= 0; i--) {
                auto wo = prev(end(ms));
                if(*wo < t[i]) {
                    wo = ms.lower_bound(t[i] - s);
                    if(wo == end(ms) or ++use > p) break;
                }
                ms.erase(wo);
            }
            
            if(ms.empty()) l = m + 1;
            else r = m - 1;
        }
        return r;
    }
};