add 1396

Author: luliyucoordinate

README.md

@@ -693,4 +693,5 @@ LeetCode
 |1391|[Check if There is a Valid Path in a Grid](https://leetcode.com/problems/check-if-there-is-a-valid-path-in-a-grid/)|c|[c++](./src/1391-Check-if-There-is-a-Valid-Path-in-a-Grid/1391.cpp)|[python](./src/1391-Check-if-There-is-a-Valid-Path-in-a-Grid/1391.py)|[go](./src/1391-Check-if-There-is-a-Valid-Path-in-a-Grid/1391.go)|[js](./src/1391-Check-if-There-is-a-Valid-Path-in-a-Grid/1391.js)|[java](./src/1391-Check-if-There-is-a-Valid-Path-in-a-Grid/1391.java)|Medium|
 |1392|[Longest Happy Prefix](https://leetcode.com/problems/longest-happy-prefix/)|c|[c++](./src/1392-Longest-Happy-Prefix/1392.cpp)|[python](./src/1392-Longest-Happy-Prefix/1392.py)|[go](./src/1392-Longest-Happy-Prefix/1392.go)|[js](./src/1392-Longest-Happy-Prefix/1392.js)|[java](./src/1392-Longest-Happy-Prefix/1392.java)|Hard|
 |1394|[Find Lucky Integer in an Array](https://leetcode.com/problems/find-lucky-integer-in-an-array/)|c|[c++](./src/1394-Find-Lucky-Integer-in-an-Array/1394.cpp)|[python](./src/1394-Find-Lucky-Integer-in-an-Array/1394.py)|[go](./src/1394-Find-Lucky-Integer-in-an-Array/1394.go)|[js](./src/1394-Find-Lucky-Integer-in-an-Array/1394.js)|[java](./src/1394-Find-Lucky-Integer-in-an-Array/1394.java)|Easy|
-|1395|[Count Number of Teams](https://leetcode.com/problems/count-number-of-teams/)|c|[c++](./src/1395-Count-Number-of-Teams/1395.cpp)|[python](./src/1395-Count-Number-of-Teams/1395.py)|[go](./src/1395-Count-Number-of-Teams/1395.go)|[js](./src/1395-Count-Number-of-Teams/1395.js)|[java](./src/1395-Count-Number-of-Teams/1395.java)|Medium|
+|1395|[Count Number of Teams](https://leetcode.com/problems/count-number-of-teams/)|c|[c++](./src/1395-Count-Number-of-Teams/1395.cpp)|[python](./src/1395-Count-Number-of-Teams/1395.py)|[go](./src/1395-Count-Number-of-Teams/1395.go)|[js](./src/1395-Count-Number-of-Teams/1395.js)|[java](./src/1395-Count-Number-of-Teams/1395.java)|Medium|
+|1396|[Design Underground System](https://leetcode.com/problems/design-underground-system/)|c|[c++](./src/1396-Design-Underground-System/1396.cpp)|[python](./src/1396-Design-Underground-System/1396.py)|[go](./src/1396-Design-Underground-System/1396.go)|[js](./src/1396-Design-Underground-System/1396.js)|[java](./src/1396-Design-Underground-System/1396.java)|Medium|

src/1396-Design-Underground-System/1396.cpp

@@ -0,0 +1,21 @@
+class UndergroundSystem {
+public:
+    void checkIn(int id, string startStation, int timeIn) {
+        check_in[id] = {startStation, timeIn};
+    }
+    
+    void checkOut(int id, string endStation, int timeOut) {
+        const auto &[startStation, timeIn] = check_in[id];
+        auto &[avg, cnt] = check_out[startStation + ">" + endStation];
+        avg += timeOut - timeIn;
+        ++cnt;
+    }
+    
+    double getAverageTime(string startStation, string endStation) {
+        auto [avg, cnt] = check_out[startStation + ">" + endStation];
+        return (double)avg / cnt;
+    }
+private:
+    unordered_map<int, pair<string, int>> check_in;
+    unordered_map<string, pair<int, int>> check_out;
+};

src/1396-Design-Underground-System/1396.go

@@ -0,0 +1,32 @@
+type UndergroundSystem struct {
+    check_in map[int]in
+    check_out map[string][2]int
+}
+
+type in struct {
+    station string
+    time int
+}
+
+func Constructor() UndergroundSystem {
+    return UndergroundSystem{check_in: make(map[int]in), check_out: make(map[string][2]int)}
+}
+
+
+func (this *UndergroundSystem) CheckIn(id int, stationName string, t int)  {
+    this.check_in[id] = in{station: stationName, time: t}
+}
+
+
+func (this *UndergroundSystem) CheckOut(id int, stationName string, t int)  {
+    start := this.check_in[id]
+    name := start.station + ">" + stationName
+    cur := this.check_out[name]
+    this.check_out[name] = [2]int{cur[0] + t - start.time, cur[1] + 1}
+}
+
+
+func (this *UndergroundSystem) GetAverageTime(startStation string, endStation string) float64 {
+    name := startStation + ">" + endStation
+    return float64(this.check_out[name][0]) / float64(this.check_out[name][1])
+}

src/1396-Design-Underground-System/1396.java

@@ -0,0 +1,25 @@
+class UndergroundSystem {
+
+    HashMap<String, Pair<Integer, Integer>> check_out = new HashMap(); 
+    HashMap<Integer, Pair<String, Integer>> check_in = new HashMap(); 
+    
+	public UndergroundSystem() {}
+    
+	public void checkIn(int id, String stationName, int t) {
+        check_in.put(id, new Pair(stationName, t));
+    }
+    
+	public void checkOut(int id, String stationName, int t) {
+        Pair<String, Integer> checkIn = check_in.get(id);
+        String name = checkIn.getKey() + ">" + stationName;
+        int totalTime = t - checkIn.getValue();
+        Pair<Integer, Integer> checkout = check_out.getOrDefault(name, new Pair(0, 0));
+        check_out.put(name, new Pair<>(checkout.getKey() + totalTime, checkout.getValue() + 1));
+    }
+    
+	public double getAverageTime(String startStation, String endStation) {
+        String name = startStation + ">" + endStation;
+        Pair<Integer, Integer> checkout = check_out.get(name);
+        return (double) checkout.getKey() / checkout.getValue();
+    }
+}

src/1396-Design-Underground-System/1396.js

@@ -0,0 +1,39 @@
+
+var UndergroundSystem = function() {
+    this.check_in = new Map();
+    this.check_out = new Map();
+};
+
+/** 
+ * @param {number} id 
+ * @param {string} stationName 
+ * @param {number} t
+ * @return {void}
+ */
+UndergroundSystem.prototype.checkIn = function(id, stationName, t) {
+    this.check_in.set(id, [stationName, t]);
+};
+
+/** 
+ * @param {number} id 
+ * @param {string} stationName 
+ * @param {number} t
+ * @return {void}
+ */
+UndergroundSystem.prototype.checkOut = function(id, stationName, t) {
+    let [startName, timeIn] = this.check_in.get(id);
+    let name = startName + ">" + stationName;
+    if (!this.check_out.has(name)) this.check_out.set(name, [0, 0]);
+    let [avg, cnt] = this.check_out.get(name);
+    this.check_out.set(name, [avg + t - timeIn, cnt + 1]);
+};
+
+/** 
+ * @param {string} startStation 
+ * @param {string} endStation
+ * @return {number}
+ */
+UndergroundSystem.prototype.getAverageTime = function(startStation, endStation) {
+    let name = startStation + ">" + endStation;
+    return this.check_out.get(name)[0] / this.check_out.get(name)[1];
+};

src/1396-Design-Underground-System/1396.py

@@ -0,0 +1,23 @@
+class UndergroundSystem:
+
+    def __init__(self):
+        self.check_in = collections.defaultdict(list)
+        self.check_out = collections.defaultdict(list)
+
+
+    def checkIn(self, id: int, stationName: str, t: int) -> None:
+        self.check_in[id] = [stationName, t]
+
+
+    def checkOut(self, id: int, stationName: str, t: int) -> None:
+        startName, timeIn = self.check_in[id]
+        name = startName + ">" + stationName
+        if not self.check_out[name]: 
+            self.check_out[name] = [0, 0]
+        self.check_out[name][0] += t - timeIn
+        self.check_out[name][1] += 1
+
+
+    def getAverageTime(self, startStation: str, endStation: str) -> float:
+        name = startStation + ">" + endStation
+        return self.check_out[name][0] / self.check_out[name][1]

src/addProb.py

@@ -2,9 +2,9 @@
 import os, bisect
 
 # 题目名称
-name = "Count Number of Teams"
-ID = 1395
-url = "https://leetcode.com/problems/count-number-of-teams/"
+name = "Design Underground System"
+ID = 1396
+url = "https://leetcode.com/problems/design-underground-system/"
 difficult = "Medium"
 prog = ['c', 'cpp', 'py', 'go', 'js', 'java']