feat: add solutions to lc problem: No.0759 (#4805)

Author: yanglbme

solution/0700-0799/0759.Employee Free Time/README.md

@@ -68,32 +68,237 @@ tags:
 
 <!-- solution:start -->
 
-### 方法一
+### 方法一：区间合并
+
+我们可以将所有员工的工作时间区间合并成一个列表，然后对该列表进行排序并合并重叠的区间。最后，遍历合并后的区间列表，找出相邻区间之间的空闲时间段。
+
+时间复杂度 $O(m \times n \times \log(m \times n))$，空间复杂度 $O(m \times n)$。其中 $m$ 和 $n$ 分别为员工数量和每个员工的工作时间区间数量。
 
 <!-- tabs:start -->
 
 #### Python3
 
 ```python
-
+"""
+# Definition for an Interval.
+class Interval:
+    def __init__(self, start: int = None, end: int = None):
+        self.start = start
+        self.end = end
+"""
+
+
+class Solution:
+    def employeeFreeTime(self, schedule: "[[Interval]]") -> "[Interval]":
+        intervals = []
+        for e in schedule:
+            intervals.extend(e)
+        intervals.sort(key=lambda x: (x.start, x.end))
+        merged = [intervals[0]]
+        for x in intervals[1:]:
+            if merged[-1].end < x.start:
+                merged.append(x)
+            else:
+                merged[-1].end = max(merged[-1].end, x.end)
+        ans = []
+        for a, b in pairwise(merged):
+            ans.append(Interval(a.end, b.start))
+        return ans
 ```
 
 #### Java
 
 ```java
-
+/*
+// Definition for an Interval.
+class Interval {
+    public int start;
+    public int end;
+
+    public Interval() {}
+
+    public Interval(int _start, int _end) {
+        start = _start;
+        end = _end;
+    }
+};
+*/
+
+class Solution {
+    public List<Interval> employeeFreeTime(List<List<Interval>> schedule) {
+        List<Interval> intervals = new ArrayList<>();
+        for (List<Interval> e : schedule) {
+            intervals.addAll(e);
+        }
+
+        intervals.sort((a, b) -> a.start == b.start ? a.end - b.end : a.start - b.start);
+
+        List<Interval> merged = new ArrayList<>();
+        merged.add(intervals.get(0));
+        for (int i = 1; i < intervals.size(); ++i) {
+            Interval last = merged.get(merged.size() - 1);
+            Interval cur = intervals.get(i);
+            if (last.end < cur.start) {
+                merged.add(cur);
+            } else {
+                last.end = Math.max(last.end, cur.end);
+            }
+        }
+
+        List<Interval> ans = new ArrayList<>();
+        for (int i = 1; i < merged.size(); ++i) {
+            Interval a = merged.get(i - 1);
+            Interval b = merged.get(i);
+            ans.add(new Interval(a.end, b.start));
+        }
+
+        return ans;
+    }
+}
 ```
 
 #### C++
 
 ```cpp
-
+/*
+// Definition for an Interval.
+class Interval {
+public:
+    int start;
+    int end;
+
+    Interval() {}
+
+    Interval(int _start, int _end) {
+        start = _start;
+        end = _end;
+    }
+};
+*/
+
+class Solution {
+public:
+    vector<Interval> employeeFreeTime(vector<vector<Interval>> schedule) {
+        vector<Interval> intervals;
+        for (auto& e : schedule) {
+            intervals.insert(intervals.end(), e.begin(), e.end());
+        }
+
+        sort(intervals.begin(), intervals.end(), [](const Interval& a, const Interval& b) {
+            if (a.start == b.start) return a.end < b.end;
+            return a.start < b.start;
+        });
+
+        vector<Interval> merged;
+        merged.push_back(intervals[0]);
+        for (int i = 1; i < intervals.size(); ++i) {
+            auto& last = merged.back();
+            auto& cur = intervals[i];
+            if (last.end < cur.start) {
+                merged.push_back(cur);
+            } else {
+                last.end = max(last.end, cur.end);
+            }
+        }
+
+        vector<Interval> ans;
+        for (int i = 1; i < merged.size(); ++i) {
+            auto& a = merged[i - 1];
+            auto& b = merged[i];
+            ans.emplace_back(a.end, b.start);
+        }
+
+        return ans;
+    }
+};
 ```
 
 #### Go
 
 ```go
+/**
+ * Definition for an Interval.
+ * type Interval struct {
+ *     Start int
+ *     End   int
+ * }
+ */
+
+func employeeFreeTime(schedule [][]*Interval) []*Interval {
+	var intervals []*Interval
+	for _, e := range schedule {
+		intervals = append(intervals, e...)
+	}
+
+	sort.Slice(intervals, func(i, j int) bool {
+		if intervals[i].Start == intervals[j].Start {
+			return intervals[i].End < intervals[j].End
+		}
+		return intervals[i].Start < intervals[j].Start
+	})
+
+	merged := []*Interval{intervals[0]}
+	for _, cur := range intervals[1:] {
+		last := merged[len(merged)-1]
+		if last.End < cur.Start {
+			merged = append(merged, cur)
+		} else if cur.End > last.End {
+			last.End = cur.End
+		}
+	}
+
+	var ans []*Interval
+	for i := 1; i < len(merged); i++ {
+		a, b := merged[i-1], merged[i]
+		ans = append(ans, &Interval{Start: a.End, End: b.Start})
+	}
+
+	return ans
+}
+```
 
+#### TypeScript
+
+```ts
+/**
+ * // Definition for an Interval.
+ * class Interval {
+ *    start: number;
+ *    end: number;
+ *    constructor(start: number, end: number) {
+ *        this.start = start;
+ *        this.end = end;
+ *    }
+ * }
+ */
+function employeeFreeTime(schedule: Interval[][]): Interval[] {
+    const intervals: Interval[] = [];
+    for (const e of schedule) {
+        intervals.push(...e);
+    }
+
+    intervals.sort((a, b) => (a.start === b.start ? a.end - b.end : a.start - b.start));
+
+    const merged: Interval[] = [intervals[0]];
+    for (let i = 1; i < intervals.length; ++i) {
+        const last = merged[merged.length - 1];
+        const cur = intervals[i];
+        if (last.end < cur.start) {
+            merged.push(cur);
+        } else {
+            last.end = Math.max(last.end, cur.end);
+        }
+    }
+
+    const ans: Interval[] = [];
+    for (let i = 1; i < merged.length; ++i) {
+        const a = merged[i - 1];
+        const b = merged[i];
+        ans.push(new Interval(a.end, b.start));
+    }
+
+    return ans;
+}
 ```
 
 <!-- tabs:end -->