Skip to content

feat: add solutions to lc problem: No.2145 #3511

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Sep 11, 2024
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
62 changes: 41 additions & 21 deletions solution/2100-2199/2145.Count the Hidden Sequences/README.md
Original file line number Diff line number Diff line change
Expand Up @@ -85,7 +85,13 @@ tags:

<!-- solution:start -->

### 方法一
### 方法一:前缀和

由于数组 $\textit{differences}$ 已经确定,那么数组 $\textit{hidden}$ 的元素最大值与最小值之差也是固定的,我们只要确保差值不超过 $\textit{upper} - \textit{lower}$ 即可。

我们不妨假设数组 $\textit{hidden}$ 的第一个元素为 $0$,那么 $\textit{hidden}[i] = \textit{hidden}[i - 1] + \textit{differences}[i - 1]$,其中 $1 \leq i \leq n$。记数组 $\textit{hidden}$ 的最大值为 $mx$,最小值为 $mi$,如果 $mx - mi \leq \textit{upper} - \textit{lower}$,那么我们就可以构造出一个合法的 $\textit{hidden}$ 数组,可以构造的个数为 $\textit{upper} - \textit{lower} - (mx - mi) + 1$。否则,无法构造出合法的 $\textit{hidden}$ 数组,返回 $0$。

时间复杂度 $O(n)$,其中 $n$ 是数组 $\textit{differences}$ 的长度。空间复杂度 $O(1)$。

<!-- tabs:start -->

Expand All @@ -94,26 +100,26 @@ tags:
```python
class Solution:
def numberOfArrays(self, differences: List[int], lower: int, upper: int) -> int:
num = mi = mx = 0
x = mi = mx = 0
for d in differences:
num += d
mi = min(mi, num)
mx = max(mx, num)
return max(0, upper - lower - (mx - mi) + 1)
x += d
mi = min(mi, x)
mx = max(mx, x)
return max(upper - lower - (mx - mi) + 1, 0)
```

#### Java

```java
class Solution {
public int numberOfArrays(int[] differences, int lower, int upper) {
long num = 0, mi = 0, mx = 0;
long x = 0, mi = 0, mx = 0;
for (int d : differences) {
num += d;
mi = Math.min(mi, num);
mx = Math.max(mx, num);
x += d;
mi = Math.min(mi, x);
mx = Math.max(mx, x);
}
return Math.max(0, (int) (upper - lower - (mx - mi) + 1));
return (int) Math.max(upper - lower - (mx - mi) + 1, 0);
}
}
```
Expand All @@ -124,13 +130,13 @@ class Solution {
class Solution {
public:
int numberOfArrays(vector<int>& differences, int lower, int upper) {
long long num = 0, mi = 0, mx = 0;
for (int& d : differences) {
num += d;
mi = min(mi, num);
mx = max(mx, num);
long long x = 0, mi = 0, mx = 0;
for (int d : differences) {
x += d;
mi = min(mi, x);
mx = max(mx, x);
}
return max(0, (int) (upper - lower - (mx - mi) + 1));
return max(upper - lower - (mx - mi) + 1, 0LL);
}
};
```
Expand All @@ -139,16 +145,30 @@ public:

```go
func numberOfArrays(differences []int, lower int, upper int) int {
num, mi, mx := 0, 0, 0
x, mi, mx := 0, 0, 0
for _, d := range differences {
num += d
mi = min(mi, num)
mx = max(mx, num)
x += d
mi = min(mi, x)
mx = max(mx, x)
}
return max(0, upper-lower-(mx-mi)+1)
}
```

#### TypeScript

```ts
function numberOfArrays(differences: number[], lower: number, upper: number): number {
let [x, mi, mx] = [0, 0, 0];
for (const d of differences) {
x += d;
mi = Math.min(mi, x);
mx = Math.max(mx, x);
}
return Math.max(0, upper - lower - (mx - mi) + 1);
}
```

<!-- tabs:end -->

<!-- solution:end -->
Expand Down
62 changes: 41 additions & 21 deletions solution/2100-2199/2145.Count the Hidden Sequences/README_EN.md
Original file line number Diff line number Diff line change
Expand Up @@ -86,7 +86,13 @@ Thus, we return 4.

<!-- solution:start -->

### Solution 1
### Solution 1: Prefix Sum

Since the array $\textit{differences}$ is already determined, the difference between the maximum and minimum values of the elements in the array $\textit{hidden}$ is also fixed. We just need to ensure that this difference does not exceed $\textit{upper} - \textit{lower}$.

Let's assume the first element of the array $\textit{hidden}$ is $0$. Then, $\textit{hidden}[i] = \textit{hidden}[i - 1] + \textit{differences}[i - 1]$, where $1 \leq i \leq n$. Let the maximum value of the array $\textit{hidden}$ be $mx$ and the minimum value be $mi$. If $mx - mi \leq \textit{upper} - \textit{lower}$, then we can construct a valid $\textit{hidden}$ array. The number of possible constructions is $\textit{upper} - \textit{lower} - (mx - mi) + 1$. Otherwise, it is impossible to construct a valid $\textit{hidden}$ array, and we return $0$.

The time complexity is $O(n)$, where $n$ is the length of the array $\textit{differences}$. The space complexity is $O(1)$.

<!-- tabs:start -->

Expand All @@ -95,26 +101,26 @@ Thus, we return 4.
```python
class Solution:
def numberOfArrays(self, differences: List[int], lower: int, upper: int) -> int:
num = mi = mx = 0
x = mi = mx = 0
for d in differences:
num += d
mi = min(mi, num)
mx = max(mx, num)
return max(0, upper - lower - (mx - mi) + 1)
x += d
mi = min(mi, x)
mx = max(mx, x)
return max(upper - lower - (mx - mi) + 1, 0)
```

#### Java

```java
class Solution {
public int numberOfArrays(int[] differences, int lower, int upper) {
long num = 0, mi = 0, mx = 0;
long x = 0, mi = 0, mx = 0;
for (int d : differences) {
num += d;
mi = Math.min(mi, num);
mx = Math.max(mx, num);
x += d;
mi = Math.min(mi, x);
mx = Math.max(mx, x);
}
return Math.max(0, (int) (upper - lower - (mx - mi) + 1));
return (int) Math.max(upper - lower - (mx - mi) + 1, 0);
}
}
```
Expand All @@ -125,13 +131,13 @@ class Solution {
class Solution {
public:
int numberOfArrays(vector<int>& differences, int lower, int upper) {
long long num = 0, mi = 0, mx = 0;
for (int& d : differences) {
num += d;
mi = min(mi, num);
mx = max(mx, num);
long long x = 0, mi = 0, mx = 0;
for (int d : differences) {
x += d;
mi = min(mi, x);
mx = max(mx, x);
}
return max(0, (int) (upper - lower - (mx - mi) + 1));
return max(upper - lower - (mx - mi) + 1, 0LL);
}
};
```
Expand All @@ -140,16 +146,30 @@ public:

```go
func numberOfArrays(differences []int, lower int, upper int) int {
num, mi, mx := 0, 0, 0
x, mi, mx := 0, 0, 0
for _, d := range differences {
num += d
mi = min(mi, num)
mx = max(mx, num)
x += d
mi = min(mi, x)
mx = max(mx, x)
}
return max(0, upper-lower-(mx-mi)+1)
}
```

#### TypeScript

```ts
function numberOfArrays(differences: number[], lower: number, upper: number): number {
let [x, mi, mx] = [0, 0, 0];
for (const d of differences) {
x += d;
mi = Math.min(mi, x);
mx = Math.max(mx, x);
}
return Math.max(0, upper - lower - (mx - mi) + 1);
}
```

<!-- tabs:end -->

<!-- solution:end -->
Expand Down
14 changes: 7 additions & 7 deletions solution/2100-2199/2145.Count the Hidden Sequences/Solution.cpp
Original file line number Diff line number Diff line change
@@ -1,12 +1,12 @@
class Solution {
public:
int numberOfArrays(vector<int>& differences, int lower, int upper) {
long long num = 0, mi = 0, mx = 0;
for (int& d : differences) {
num += d;
mi = min(mi, num);
mx = max(mx, num);
long long x = 0, mi = 0, mx = 0;
for (int d : differences) {
x += d;
mi = min(mi, x);
mx = max(mx, x);
}
return max(0, (int) (upper - lower - (mx - mi) + 1));
return max(upper - lower - (mx - mi) + 1, 0LL);
}
};
};
10 changes: 5 additions & 5 deletions solution/2100-2199/2145.Count the Hidden Sequences/Solution.go
Original file line number Diff line number Diff line change
@@ -1,9 +1,9 @@
func numberOfArrays(differences []int, lower int, upper int) int {
num, mi, mx := 0, 0, 0
x, mi, mx := 0, 0, 0
for _, d := range differences {
num += d
mi = min(mi, num)
mx = max(mx, num)
x += d
mi = min(mi, x)
mx = max(mx, x)
}
return max(0, upper-lower-(mx-mi)+1)
}
}
12 changes: 6 additions & 6 deletions solution/2100-2199/2145.Count the Hidden Sequences/Solution.java
Original file line number Diff line number Diff line change
@@ -1,11 +1,11 @@
class Solution {
public int numberOfArrays(int[] differences, int lower, int upper) {
long num = 0, mi = 0, mx = 0;
long x = 0, mi = 0, mx = 0;
for (int d : differences) {
num += d;
mi = Math.min(mi, num);
mx = Math.max(mx, num);
x += d;
mi = Math.min(mi, x);
mx = Math.max(mx, x);
}
return Math.max(0, (int) (upper - lower - (mx - mi) + 1));
return (int) Math.max(upper - lower - (mx - mi) + 1, 0);
}
}
}
10 changes: 5 additions & 5 deletions solution/2100-2199/2145.Count the Hidden Sequences/Solution.py
Original file line number Diff line number Diff line change
@@ -1,8 +1,8 @@
class Solution:
def numberOfArrays(self, differences: List[int], lower: int, upper: int) -> int:
num = mi = mx = 0
x = mi = mx = 0
for d in differences:
num += d
mi = min(mi, num)
mx = max(mx, num)
return max(0, upper - lower - (mx - mi) + 1)
x += d
mi = min(mi, x)
mx = max(mx, x)
return max(upper - lower - (mx - mi) + 1, 0)
Original file line number Diff line number Diff line change
@@ -0,0 +1,9 @@
function numberOfArrays(differences: number[], lower: number, upper: number): number {
let [x, mi, mx] = [0, 0, 0];
for (const d of differences) {
x += d;
mi = Math.min(mi, x);
mx = Math.max(mx, x);
}
return Math.max(0, upper - lower - (mx - mi) + 1);
}
Loading