Create the-latest-time-to-catch-a-bus.cpp

Author: kamyu104

C++/the-latest-time-to-catch-a-bus.cpp

@@ -0,0 +1,35 @@
+// Time:  O(nlogn + mlogm)
+// Space: O(1)
+
+// sort, two pointers
+class Solution {
+public:
+    int latestTimeCatchTheBus(vector<int>& buses, vector<int>& passengers, int capacity) {
+        sort(begin(buses), end(buses));
+        sort(begin(passengers), end(passengers));
+        int cnt = 0, j = 0;
+        for (int i = 0; i < size(buses) - 1; ++i) {
+            while (j < size(passengers) && passengers[j] <= buses[i]) {
+                ++cnt;
+                ++j;
+            }
+            cnt = max(cnt-capacity, 0);
+        }
+        j -= max(cnt - capacity, 0);
+        cnt = min(cnt, capacity);
+        while (j < size(passengers) && passengers[j] <= buses.back() && cnt + 1 <= capacity) {
+            ++cnt;
+            ++j;
+        }
+        if (cnt < capacity && (j - 1 < 0 || passengers[j - 1] != buses.back())) {
+            return buses.back();
+        }
+        --j;
+        for (; j; --j) {
+            if (passengers[j] - 1 != passengers[j - 1]) {
+                break;
+            }
+        }
+        return passengers[j] - 1;
+    }
+};