The Latest Time to Catch a Bus.java

// Runtime: 59 ms (Top 40.13%) | Memory: 106.7 MB (Top 13.12%)
class Solution {
    public int latestTimeCatchTheBus(int[] buses, int[] passengers, int capacity) {
        Arrays.sort(buses);
        Arrays.sort(passengers);
        HashSet<Integer> set = new HashSet<>();
        for(int val : passengers){
            set.add(val);
        }
        int n = buses.length;
        int m = passengers.length;
        int solb = capacity; // solb = space on last bus
        int lastPerson = 0;
        int i = 0, j = 0;
        while(i < n && j < m){
            int cc = capacity; // cc => current capacity;
            while(j < m && cc > 0 && buses[i] >= passengers[j]){
                cc--;
                lastPerson = passengers[j];
                j++;
            }
            i++;
            solb = cc;
        }
        int x = lastPerson;
        if(solb > 0 || i != n){
            x = buses[n - 1];
        }
        while(set.contains(x) == true){
            x--;
        }
        return x;
    }
}