Create find-right-interval.cpp

Author: kamyu104

C++/find-right-interval.cpp

@@ -0,0 +1,31 @@
+// Time:  O(nlogn)
+// Space: O(n)
+
+/**
+ * Definition for an interval.
+ * struct Interval {
+ *     int start;
+ *     int end;
+ *     Interval() : start(0), end(0) {}
+ *     Interval(int s, int e) : start(s), end(e) {}
+ * };
+ */
+class Solution {
+public:
+    vector<int> findRightInterval(vector<Interval>& intervals) {
+        map<int, int> lookup;
+        vector<int> result;
+        for (int i = 0; i < intervals.size(); ++i) {
+            lookup[intervals[i].start] = i;
+        }
+        for (const auto& interval : intervals) {
+            const auto it = lookup.lower_bound(interval.end);
+            if (it == lookup.end()) {
+                result.emplace_back(-1);
+            } else {
+                result.emplace_back(it->second);
+            }
+        }
+        return result;
+    }
+};