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feat: add solutions to lc problem: No.1732
No.1732.Find the Highest Altitude
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‎solution/1700-1799/1732.Find the Highest Altitude/README.md

Lines changed: 63 additions & 30 deletions
Original file line numberDiff line numberDiff line change
@@ -42,7 +42,25 @@
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<!-- 这里可写通用的实现逻辑 -->
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45-
求前 N 项和的最大值即可。
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**方法一：前缀和（差分数组）**
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我们假设每个点的海拔为 $h_i$，由于 $gain[i]$ 表示第 $i$ 个点和第 $i + 1$ 个点的海拔差，因此 $gain[i] = h_{i + 1} - h_i$。那么：
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$$
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\sum_{i = 0}^{n-1} gain[i] = h_1 - h_0 + h_2 - h_1 + \cdots + h_n - h_{n - 1} = h_n - h_0 = h_n
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$$
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即：
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$$
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h_{i+1} = \sum_{j = 0}^{i} gain[j]
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$$
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可以发现，每个点的海拔都可以通过前缀和的方式计算出来。因此，我们只需要遍历一遍数组，求出前缀和的最大值，即为最高点的海拔。
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> 实际上题目中的 $gain$ 数组是一个差分数组，对差分数组求前缀和即可得到原海拔数组。然后求出原海拔数组的最大值即可。
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时间复杂度 $O(n)$，空间复杂度 $O(1)$。其中 $n$ 为数组 $gain$ 的长度。
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<!-- tabs:start -->
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@@ -53,11 +71,17 @@
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```python
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class Solution:
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def largestAltitude(self, gain: List[int]) -> int:
56-
res = t = 0
57-
for h in gain:
58-
t += h
59-
res = max(res, t)
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return res
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return max(accumulate(gain, initial=0))
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```
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```python
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class Solution:
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def largestAltitude(self, gain: List[int]) -> int:
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ans = s = 0
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for v in gain:
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s += v
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ans = max(ans, s)
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return ans
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```
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### **Java**
@@ -67,13 +91,12 @@ class Solution:
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```java
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class Solution {
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public int largestAltitude(int[] gain) {
70-
int res = 0;
71-
int t = 0;
72-
for (int h : gain) {
73-
t += h;
74-
res = Math.max(res, t);
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int ans = 0, s = 0;
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for (int v : gain) {
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s += v;
97+
ans = Math.max(ans, s);
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}
76-
return res;
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return ans;
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}
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}
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```
@@ -84,34 +107,44 @@ class Solution {
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class Solution {
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public:
86109
int largestAltitude(vector<int>& gain) {
87-
int res = 0, t = 0;
88-
for (int h : gain) {
89-
t += h;
90-
res = max(res, t);
91-
}
92-
return res;
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int ans = 0, s = 0;
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for (int v : gain) s += v, ans = max(ans, s);
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return ans;
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}
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};
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```
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### **Go**
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```go
100-
func largestAltitude(gain []int) int {
101-
res, t := 0, 0
102-
for _, h := range gain {
103-
t += h
104-
res = max(res, t)
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func largestAltitude(gain []int) (ans int) {
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s := 0
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for _, v := range gain {
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s += v
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if ans < s {
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ans = s
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}
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}
106-
return res
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return
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}
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```
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109-
func max(a, b int) int {
110-
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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### **JavaScript**
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```js
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/**
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* @param {number[]} gain
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* @return {number}
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*/
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var largestAltitude = function (gain) {
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let ans = 0;
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let s = 0;
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for (const v of gain) {
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s += v;
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ans = Math.max(ans, s);
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}
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return ans;
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};
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```
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### **...**

‎solution/1700-1799/1732.Find the Highest Altitude/README_EN.md

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Original file line numberDiff line numberDiff line change
@@ -43,25 +43,30 @@
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```python
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class Solution:
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def largestAltitude(self, gain: List[int]) -> int:
46-
res = t = 0
47-
for h in gain:
48-
t += h
49-
res = max(res, t)
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return res
46+
return max(accumulate(gain, initial=0))
47+
```
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```python
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class Solution:
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def largestAltitude(self, gain: List[int]) -> int:
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ans = s = 0
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for v in gain:
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s += v
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ans = max(ans, s)
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return ans
5157
```
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### **Java**
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```java
5662
class Solution {
5763
public int largestAltitude(int[] gain) {
58-
int res = 0;
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int t = 0;
60-
for (int h : gain) {
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t += h;
62-
res = Math.max(res, t);
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int ans = 0, s = 0;
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for (int v : gain) {
66+
s += v;
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ans = Math.max(ans, s);
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}
64-
return res;
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return ans;
6570
}
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}
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```
@@ -72,34 +77,44 @@ class Solution {
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class Solution {
7378
public:
7479
int largestAltitude(vector<int>& gain) {
75-
int res = 0, t = 0;
76-
for (int h : gain) {
77-
t += h;
78-
res = max(res, t);
79-
}
80-
return res;
80+
int ans = 0, s = 0;
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for (int v : gain) s += v, ans = max(ans, s);
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return ans;
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}
8284
};
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```
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### **Go**
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```go
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func largestAltitude(gain []int) int {
89-
res, t := 0, 0
90-
for _, h := range gain {
91-
t += h
92-
res = max(res, t)
90+
func largestAltitude(gain []int) (ans int) {
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s := 0
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for _, v := range gain {
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s += v
94+
if ans < s {
95+
ans = s
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}
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}
94-
return res
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return
9599
}
100+
```
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97-
func max(a, b int) int {
98-
if a > b {
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return a
100-
}
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return b
102-
}
102+
### **JavaScript**
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```js
105+
/**
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* @param {number[]} gain
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* @return {number}
108+
*/
109+
var largestAltitude = function (gain) {
110+
let ans = 0;
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let s = 0;
112+
for (const v of gain) {
113+
s += v;
114+
ans = Math.max(ans, s);
115+
}
116+
return ans;
117+
};
103118
```
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105120
### **...**

‎solution/1700-1799/1732.Find the Highest Altitude/Solution.cpp

Lines changed: 3 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -1,11 +1,8 @@
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class Solution {
22
public:
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int largestAltitude(vector<int>& gain) {
4-
int res = 0, t = 0;
5-
for (int h : gain) {
6-
t += h;
7-
res = max(res, t);
8-
}
9-
return res;
4+
int ans = 0, s = 0;
5+
for (int v : gain) s += v, ans = max(ans, s);
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return ans;
107
}
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};

‎solution/1700-1799/1732.Find the Highest Altitude/Solution.go

Lines changed: 8 additions & 13 deletions
Original file line numberDiff line numberDiff line change
@@ -1,15 +1,10 @@
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func largestAltitude(gain []int) int {
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res, t := 0, 0
3-
for _, h := range gain {
4-
t += h
5-
res = max(res, t)
1+
func largestAltitude(gain []int) (ans int) {
2+
s := 0
3+
for _, v := range gain {
4+
s += v
5+
if ans < s {
6+
ans = s
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}
68
}
7-
return res
8-
}
9-
10-
func max(a, b int) int {
11-
if a > b {
12-
return a
13-
}
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return b
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return
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}

‎solution/1700-1799/1732.Find the Highest Altitude/Solution.java

Lines changed: 5 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -1,11 +1,10 @@
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class Solution {
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public int largestAltitude(int[] gain) {
3-
int res = 0;
4-
int t = 0;
5-
for (int h : gain) {
6-
t += h;
7-
res = Math.max(res, t);
3+
int ans = 0, s = 0;
4+
for (int v : gain) {
5+
s += v;
6+
ans = Math.max(ans, s);
87
}
9-
return res;
8+
return ans;
109
}
1110
}

‎solution/1700-1799/1732.Find the Highest Altitude/Solution.js

Lines changed: 13 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,13 @@
1+
/**
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* @param {number[]} gain
3+
* @return {number}
4+
*/
5+
var largestAltitude = function (gain) {
6+
let ans = 0;
7+
let s = 0;
8+
for (const v of gain) {
9+
s += v;
10+
ans = Math.max(ans, s);
11+
}
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return ans;
13+
};

‎solution/1700-1799/1732.Find the Highest Altitude/Solution.py

Lines changed: 5 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,7 @@
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class Solution:
22
def largestAltitude(self, gain: List[int]) -> int:
3-
res = t = 0
4-
for h in gain:
5-
t += h
6-
res = max(res, t)
7-
return res
3+
ans = s = 0
4+
for v in gain:
5+
s += v
6+
ans = max(ans, s)
7+
return ans

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