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feat: add solutions to lc problem: No.2008
No.2008.Maximum Earnings From Taxi
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‎solution/1200-1299/1235.Maximum Profit in Job Scheduling/README.md

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时间复杂度 $O(n \times \log n)$,其中 $n$ 是工作的数量。
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相似题目:[1751. 最多可以参加的会议数目 II](/solution/1700-1799/1751.Maximum%20Number%20of%20Events%20That%20Can%20Be%20Attended%20II/README.md)
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相似题目:
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- [2008. 出租车的最大盈利](/solution/2000-2099/2008.Maximum%20Earnings%20From%20Taxi/README.md)
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- [1751. 最多可以参加的会议数目 II](/solution/1700-1799/1751.Maximum%20Number%20of%20Events%20That%20Can%20Be%20Attended%20II/README.md)
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‎solution/1700-1799/1751.Maximum Number of Events That Can Be Attended II/README.md

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时间复杂度 $O(n\times \log n + n\times k)$,其中 $n$ 为会议数量。
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相似题目:[1235. 规划兼职工作](/solution/1200-1299/1235.Maximum%20Profit%20in%20Job%20Scheduling/README.md)
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相似题目:
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- [1235. 规划兼职工作](/solution/1200-1299/1235.Maximum%20Profit%20in%20Job%20Scheduling/README.md)
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- [2008. 出租车的最大盈利](/solution/2000-2099/2008.Maximum%20Earnings%20From%20Taxi/README.md)
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‎solution/2000-2099/2008.Maximum Earnings From Taxi/README.md

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<!-- 这里可写通用的实现逻辑 -->
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**方法一:记忆化搜索 + 二分查找**
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我们先将 `rides` 按照 `start` 从小到大排序,然后设计一个函数 $dfs(i)$,表示从第 $i$ 个乘客开始接单,最多能获得的小费。答案即为 $dfs(0)$。
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函数 $dfs(i)$ 的计算过程如下:
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对于第 $i$ 个乘客,我们可以选择接单,也可以选择不接单。如果不接单,那么最多能获得的小费为 $dfs(i + 1)$;如果接单,那么我们可以通过二分查找,找到在第 $i$ 个乘客下车地点之后遇到的第一个乘客,记为 $j$,那么最多能获得的小费为 $dfs(j) + end_i - start_i + tip_i$。取两者的较大值即可。即:
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$$
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dfs(i) = \max(dfs(i + 1), dfs(j) + end_i - start_i + tip_i)
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$$
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其中 $j$ 是满足 $start_j \ge end_i$ 的最小的下标,可以通过二分查找得到。
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此过程中,我们可以使用记忆化搜索,将每个状态的答案保存下来,避免重复计算。
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时间复杂度 $O(m\times \log m)$,其中 $m$ 为 `rides` 的长度。
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**方法二:动态规划 + 二分查找**
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我们可以将方法一中的记忆化搜索改为动态规划。
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先将 `rides` 排序,这次我们按照 `end` 从小到大排序。然后定义 $dp[i]$,表示前 $i$ 个乘客中,最多能获得的小费。答案即为 $dp[m]$。初始化 $dp[0] = 0$。
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对于第 $i$ 个乘客,我们可以选择接单,也可以选择不接单。如果不接单,那么最多能获得的小费为 $dp[i]$;如果接单,我们可以通过二分查找,找到在第 $i$ 个乘客上车地点之前,最后一个下车地点不大于 $start_i$ 的乘客,记为 $j$,那么最多能获得的小费为 $dp[j] + end_i - start_i + tip_i$。取两者的较大值即可。即:
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$$
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dp[i] = \max(dp[i - 1], dp[j] + end_i - start_i + tip_i)
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$$
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其中 $j$ 是满足 $end_j \le start_i$ 的最大的下标,可以通过二分查找得到。
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时间复杂度 $O(m\times \log m)$,其中 $m$ 为 `rides` 的长度。
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相似题目:
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- [1235. 规划兼职工作](/solution/1200-1299/1235.Maximum%20Profit%20in%20Job%20Scheduling/README.md)
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- [1751. 最多可以参加的会议数目 II](/solution/1700-1799/1751.Maximum%20Number%20of%20Events%20That%20Can%20Be%20Attended%20II/README.md)
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### **Python3**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```python
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class Solution:
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def maxTaxiEarnings(self, n: int, rides: List[List[int]]) -> int:
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@cache
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def dfs(i):
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if i >= len(rides):
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return 0
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s, e, t = rides[i]
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j = bisect_left(rides, e, lo=i + 1, key=lambda x: x[0])
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return max(dfs(i + 1), dfs(j) + e - s + t)
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rides.sort()
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return dfs(0)
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```
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```python
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class Solution:
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def maxTaxiEarnings(self, n: int, rides: List[List[int]]) -> int:
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rides.sort(key=lambda x: x[1])
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m = len(rides)
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dp = [0] * (m + 1)
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for i, (s, e, t) in enumerate(rides):
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j = bisect_right(rides, s, hi=i, key=lambda x: x[1])
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dp[i + 1] = max(dp[i], dp[j] + e - s + t)
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return dp[m]
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```
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### **Java**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```java
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class Solution {
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private int[][] rides;
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private long[] f;
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private int m;
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public long maxTaxiEarnings(int n, int[][] rides) {
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m = rides.length;
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f = new long[m];
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Arrays.sort(rides, (a, b) -> a[0] - b[0]);
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this.rides = rides;
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return dfs(0);
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}
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private long dfs(int i) {
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if (i >= m) {
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return 0;
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}
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if (f[i] != 0) {
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return f[i];
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}
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int s = rides[i][0], e = rides[i][1], t = rides[i][2];
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int j = search(rides, e, i + 1);
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long ans = Math.max(dfs(i + 1), dfs(j) + e - s + t);
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f[i] = ans;
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return ans;
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}
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private int search(int[][] rides, int x, int i) {
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int left = i, right = m;
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while (left < right) {
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int mid = (left + right) >> 1;
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if (rides[mid][0] >= x) {
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right = mid;
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} else {
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left = mid + 1;
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}
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}
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return left;
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}
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}
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```
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```java
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class Solution {
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public long maxTaxiEarnings(int n, int[][] rides) {
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Arrays.sort(rides, (a, b) -> a[1] - b[1]);
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int m = rides.length;
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long[] dp = new long[m + 1];
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for (int i = 0; i < m; ++i) {
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int s = rides[i][0], e = rides[i][1], t = rides[i][2];
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int j = search(rides, s, i);
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dp[i + 1] = Math.max(dp[i], dp[j] + e - s + t);
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}
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return dp[m];
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}
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private int search(int[][] rides, int x, int n) {
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int left = 0, right = n;
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while (left < right) {
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int mid = (left + right) >> 1;
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if (rides[mid][1] > x) {
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right = mid;
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} else {
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left = mid + 1;
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}
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}
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return left;
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}
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}
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```
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### **C++**
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```cpp
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using ll = long long;
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class Solution {
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public:
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long long maxTaxiEarnings(int n, vector<vector<int>>& rides) {
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sort(rides.begin(), rides.end());
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int m = rides.size();
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vector<ll> f(m);
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vector<int> x(3);
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function<ll(int)> dfs = [&](int i) -> ll {
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if (i >= m) return 0;
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if (f[i]) return f[i];
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int s = rides[i][0], e = rides[i][1], t = rides[i][2];
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x[0] = e;
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int j = lower_bound(rides.begin() + i + 1, rides.end(), x, [&](auto& l, auto& r) -> bool { return l[0] < r[0];}) - rides.begin();
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ll ans = max(dfs(i + 1), dfs(j) + e - s + t);
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f[i] = ans;
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return ans;
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};
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return dfs(0);
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}
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};
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```
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```cpp
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using ll = long long;
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class Solution {
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public:
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long long maxTaxiEarnings(int n, vector<vector<int>>& rides) {
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sort(rides.begin(), rides.end(), [&](auto& l, auto& r) -> bool { return l[1] < r[1]; });
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int m = rides.size();
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vector<ll> dp(m + 1);
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vector<int> x(3);
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for (int i = 0; i < m; ++i) {
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int s = rides[i][0], e = rides[i][1], t = rides[i][2];
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x[1] = s;
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int j = upper_bound(rides.begin(), rides.begin() + i, x, [&](auto& l, auto& r) -> bool { return l[1] < r[1]; }) - rides.begin();
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dp[i + 1] = max(dp[i], dp[j] + e - s + t);
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}
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return dp[m];
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}
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};
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```
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### **Go**
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```go
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func maxTaxiEarnings(n int, rides [][]int) int64 {
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sort.Slice(rides, func(i, j int) bool { return rides[i][0] < rides[j][0] })
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m := len(rides)
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f := make([]int64, m)
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var dfs func(int) int64
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dfs = func(i int) int64 {
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if i >= m {
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return 0
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}
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if f[i] != 0 {
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return f[i]
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}
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s, e, t := rides[i][0], rides[i][1], rides[i][2]
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j := sort.Search(m, func(k int) bool { return rides[k][0] >= e })
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ans := max(dfs(i+1), dfs(j)+int64(e-s+t))
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f[i] = ans
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return ans
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}
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return dfs(0)
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}
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func max(a, b int64) int64 {
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if a > b {
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return a
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}
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return b
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}
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```
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```go
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func maxTaxiEarnings(n int, rides [][]int) int64 {
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sort.Slice(rides, func(i, j int) bool { return rides[i][1] < rides[j][1] })
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m := len(rides)
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dp := make([]int64, m+1)
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for i, ride := range rides {
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s, e, t := ride[0], ride[1], ride[2]
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j := sort.Search(m, func(k int) bool { return rides[k][1] > s })
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dp[i+1] = max(dp[i], dp[j]+int64(e-s+t))
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}
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return dp[m]
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}
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func max(a, b int64) int64 {
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if a > b {
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return a
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}
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return b
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}
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```
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### **...**

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