add meeting roooms

Author: tg123

meeting-rooms-ii/README.md

@@ -0,0 +1,46 @@
+/**
+ * Definition for an interval.
+ * public class Interval {
+ *     int start;
+ *     int end;
+ *     Interval() { start = 0; end = 0; }
+ *     Interval(int s, int e) { start = s; end = e; }
+ * }
+ */
+public class Solution {
+
+    static class RoomAllocator {
+
+        List<Interval> rooms = new ArrayList<>();
+
+        int currentTime = -1;
+
+        void alloc(Interval room){
+            for(int i = 0; i < rooms.size(); i++){
+                if(rooms.get(i).end <= currentTime){
+                    rooms.set(i, room);
+                    return;
+                }
+            }
+
+            rooms.add(room);
+        }
+
+        void freeBefore(int time){
+            currentTime = time;
+        }
+    }
+
+    public int minMeetingRooms(Interval[] intervals) {
+        Arrays.sort(intervals, (a, b) -> a.start - b.start);
+
+        RoomAllocator ra = new RoomAllocator();
+
+        for(Interval i : intervals){
+            ra.freeBefore(i.start);
+            ra.alloc(i);
+        }
+
+        return ra.rooms.size();
+    }
+}

meeting-rooms-ii/Solution.java

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+---
+layout: solution
+title: Meeting Rooms II
+date: 2015-08-12 20:03:46+08:00
+leetcode_id: 253
+---
+{% include_relative README.md %}

meeting-rooms-ii/index.md

@@ -0,0 +1,26 @@
+/**
+ * Definition for an interval.
+ * public class Interval {
+ *     int start;
+ *     int end;
+ *     Interval() { start = 0; end = 0; }
+ *     Interval(int s, int e) { start = s; end = e; }
+ * }
+ */
+public class Solution {
+    public boolean canAttendMeetings(Interval[] intervals) {
+        Arrays.sort(intervals, (a, b) -> a.start - b.start);
+
+        int maxend = 0;
+
+        for(Interval i : intervals){
+            if(i.start < maxend){
+                return false;
+            }
+
+            maxend = Math.max(maxend, i.end);
+        }
+
+        return true;
+    }
+}

meeting-rooms/README.md

@@ -0,0 +1,7 @@
+---
+layout: solution
+title: Meeting Rooms
+date: 2015-08-12 20:02:37+08:00
+leetcode_id: 252
+---
+{% include_relative README.md %}