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feat: add solutions to lc problem: No.2116 (#4132)
No.2116.Check if a Parentheses String Can Be Valid
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‎solution/2100-2199/2116.Check if a Parentheses String Can Be Valid/README.md

+37-5
Original file line numberDiff line numberDiff line change
@@ -94,17 +94,17 @@ tags:
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### 方法一：贪心 + 两次遍历
9696

97-
我们观察发现，奇数长度的字符串一定不是有效的括号字符串，因为无论怎么匹配，都会剩下一个括号。因此，如果字符串 $s$ 的长度是奇数，提前返回 `false`。
97+
我们观察发现，奇数长度的字符串一定不是有效的括号字符串，因为无论怎么匹配，都会剩下一个括号。因此，如果字符串 $s$ 的长度是奇数，提前返回 $\textit{false}$。
9898

9999
接下来，我们进行两次遍历。
100100

101-
第一次从左到右，判断所有的 `'('` 括号是否可以被 `')'` 或者可变括号匹配，如果不可以，直接返回 `false`。
101+
第一次从左到右，判断所有的 `'('` 括号是否可以被 `')'` 或者可变括号匹配，如果不可以，直接返回 $\textit{false}$。
102102

103-
第二次从右到左，判断所有的 `')'` 括号是否可以被 `'('` 或者可变括号匹配，如果不可以，直接返回 `false`。
103+
第二次从右到左，判断所有的 `')'` 括号是否可以被 `'('` 或者可变括号匹配，如果不可以，直接返回 $\textit{false}$。
104104

105-
遍历结束，说明所有的括号都可以被匹配，字符串 $s$ 是有效的括号字符串，返回 `true`。
105+
遍历结束，说明所有的括号都可以被匹配，字符串 $s$ 是有效的括号字符串，返回 $\textit{true}$。
106106

107-
时间复杂度 $O(n)$，空间复杂度 $O(1)$。其中 $n$ 为字符串 $s$ 的长度。
107+
时间复杂度 $O(n)$，其中 $n$ 为字符串 $s$ 的长度。空间复杂度 $O(1)$。
108108

109109
相似题目：
110110

@@ -240,6 +240,38 @@ func canBeValid(s string, locked string) bool {
240240
}
241241
```
242242

243+
#### TypeScript
244+
245+
```ts
246+
function canBeValid(s: string, locked: string): boolean {
247+
const n = s.length;
248+
if (n & 1) {
249+
return false;
250+
}
251+
let x = 0;
252+
for (let i = 0; i < n; ++i) {
253+
if (s[i] === '(' || locked[i] === '0') {
254+
++x;
255+
} else if (x > 0) {
256+
--x;
257+
} else {
258+
return false;
259+
}
260+
}
261+
x = 0;
262+
for (let i = n - 1; i >= 0; --i) {
263+
if (s[i] === ')' || locked[i] === '0') {
264+
++x;
265+
} else if (x > 0) {
266+
--x;
267+
} else {
268+
return false;
269+
}
270+
}
271+
return true;
272+
}
273+
```
274+
243275
<!-- tabs:end -->
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245277
<!-- solution:end -->

‎solution/2100-2199/2116.Check if a Parentheses String Can Be Valid/README_EN.md

+51-3
Original file line numberDiff line numberDiff line change
@@ -59,7 +59,7 @@ We change s[0] and s[4] to &#39;(&#39; while leaving s[2] and s[5] unchanged to
5959
<pre>
6060
<strong>Input:</strong> s = &quot;)&quot;, locked = &quot;0&quot;
6161
<strong>Output:</strong> false
62-
<strong>Explanation:</strong> locked permits us to change s[0].
62+
<strong>Explanation:</strong> locked permits us to change s[0].
6363
Changing s[0] to either &#39;(&#39; or &#39;)&#39; will not make s valid.
6464
</pre>
6565

@@ -68,7 +68,7 @@ Changing s[0] to either &#39;(&#39; or &#39;)&#39; will not make s valid.
6868
<pre>
6969
<strong>Input:</strong> s = &quot;(((())(((())&quot;, locked = &quot;111111010111&quot;
7070
<strong>Output:</strong> false
71-
<strong>Explanation:</strong> locked permits us to change s[6] and s[8].
71+
<strong>Explanation:</strong> locked permits us to change s[6] and s[8].
7272
We change s[6] and s[8] to &#39;)&#39; to make s valid.
7373
</pre>
7474

@@ -88,7 +88,23 @@ We change s[6] and s[8] to &#39;)&#39; to make s valid.
8888

8989
<!-- solution:start -->
9090

91-
### Solution 1
91+
### Solution 1: Greedy + Two Passes
92+
93+
We observe that a string of odd length cannot be a valid parentheses string because there will always be one unmatched parenthesis. Therefore, if the length of the string $s$ is odd, return $\textit{false}$ immediately.
94+
95+
Next, we perform two passes.
96+
97+
The first pass goes from left to right, checking if all `'('` parentheses can be matched by `')'` or changeable parentheses. If not, return $\textit{false}$.
98+
99+
The second pass goes from right to left, checking if all `')'` parentheses can be matched by `'('` or changeable parentheses. If not, return $\textit{false}$.
100+
101+
If both passes complete successfully, it means all parentheses can be matched, and the string $s$ is a valid parentheses string. Return $\textit{true}$.
102+
103+
The time complexity is $O(n)$, where $n$ is the length of the string $s$. The space complexity is $O(1)$.
104+
105+
Similar problems:
106+
107+
- [678. Valid Parenthesis String](https://github.com/doocs/leetcode/blob/main/solution/0600-0699/0678.Valid%20Parenthesis%20String/README_EN.md)
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93109
<!-- tabs:start -->
94110

@@ -220,6 +236,38 @@ func canBeValid(s string, locked string) bool {
220236
}
221237
```
222238

239+
#### TypeScript
240+
241+
```ts
242+
function canBeValid(s: string, locked: string): boolean {
243+
const n = s.length;
244+
if (n & 1) {
245+
return false;
246+
}
247+
let x = 0;
248+
for (let i = 0; i < n; ++i) {
249+
if (s[i] === '(' || locked[i] === '0') {
250+
++x;
251+
} else if (x > 0) {
252+
--x;
253+
} else {
254+
return false;
255+
}
256+
}
257+
x = 0;
258+
for (let i = n - 1; i >= 0; --i) {
259+
if (s[i] === ')' || locked[i] === '0') {
260+
++x;
261+
} else if (x > 0) {
262+
--x;
263+
} else {
264+
return false;
265+
}
266+
}
267+
return true;
268+
}
269+
```
270+
223271
<!-- tabs:end -->
224272

225273
<!-- solution:end -->

‎solution/2100-2199/2116.Check if a Parentheses String Can Be Valid/Solution.ts

+27
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,27 @@
1+
function canBeValid(s: string, locked: string): boolean {
2+
const n = s.length;
3+
if (n & 1) {
4+
return false;
5+
}
6+
let x = 0;
7+
for (let i = 0; i < n; ++i) {
8+
if (s[i] === '(' || locked[i] === '0') {
9+
++x;
10+
} else if (x > 0) {
11+
--x;
12+
} else {
13+
return false;
14+
}
15+
}
16+
x = 0;
17+
for (let i = n - 1; i >= 0; --i) {
18+
if (s[i] === ')' || locked[i] === '0') {
19+
++x;
20+
} else if (x > 0) {
21+
--x;
22+
} else {
23+
return false;
24+
}
25+
}
26+
return true;
27+
}

‎solution/2100-2199/2117.Abbreviating the Product of a Range/README.md

+19-67
Original file line numberDiff line numberDiff line change
@@ -64,8 +64,8 @@ tags:
6464
<strong>输入：</strong>left = 2, right = 11
6565
<strong>输出：</strong>"399168e2"
6666
<strong>解释：</strong>乘积为 39916800 。
67-
有 2 个后缀 0 ，删除后得到 399168 。缩写的结尾为 "e2" 。
68-
删除后缀 0 后是 6 位数，不需要进一步缩写。
67+
有 2 个后缀 0 ，删除后得到 399168 。缩写的结尾为 "e2" 。
68+
删除后缀 0 后是 6 位数，不需要进一步缩写。
6969
所以，最终将乘积表示为 "399168e2" 。
7070
</pre>
7171

@@ -98,39 +98,36 @@ tags:
9898
#### Python3
9999

100100
```python
101-
import numpy
102-
103-
104101
class Solution:
105102
def abbreviateProduct(self, left: int, right: int) -> str:
106103
cnt2 = cnt5 = 0
107-
z = numpy.float128(0)
108104
for x in range(left, right + 1):
109-
z += numpy.log10(x)
110105
while x % 2 == 0:
111-
x //= 2
112106
cnt2 += 1
107+
x //= 2
113108
while x % 5 == 0:
114-
x //= 5
115109
cnt5 += 1
110+
x //= 5
116111
c = cnt2 = cnt5 = min(cnt2, cnt5)
117-
suf = y = 1
112+
pre = suf = 1
118113
gt = False
119114
for x in range(left, right + 1):
120-
while cnt2 and x % 2 == 0:
121-
x //= 2
115+
suf *= x
116+
while cnt2 and suf % 2 == 0:
117+
suf //= 2
122118
cnt2 -= 1
123-
while cnt5 and x % 5 == 0:
124-
x //= 5
119+
while cnt5 and suf % 5 == 0:
120+
suf //= 5
125121
cnt5 -= 1
126-
suf = suf * x % 100000
127-
if not gt:
128-
y *= x
129-
gt = y >= 1e10
130-
if not gt:
131-
return str(y) + "e" + str(c)
132-
pre = int(pow(10, z - int(z) + 4))
133-
return str(pre) + "..." + str(suf).zfill(5) + "e" + str(c)
122+
if suf >= 1e10:
123+
gt = True
124+
suf %= int(1e10)
125+
pre *= x
126+
while pre > 1e5:
127+
pre /= 10
128+
if gt:
129+
return str(int(pre)) + "..." + str(suf % int(1e5)).zfill(5) + "e" + str(c)
130+
return str(suf) + "e" + str(c)
134131
```
135132

136133
#### Java
@@ -271,49 +268,4 @@ func abbreviateProduct(left int, right int) string {
271268

272269
<!-- solution:end -->
273270

274-
<!-- solution:start -->
275-
276-
### 方法二
277-
278-
<!-- tabs:start -->
279-
280-
#### Python3
281-
282-
```python
283-
class Solution:
284-
def abbreviateProduct(self, left: int, right: int) -> str:
285-
cnt2 = cnt5 = 0
286-
for x in range(left, right + 1):
287-
while x % 2 == 0:
288-
cnt2 += 1
289-
x //= 2
290-
while x % 5 == 0:
291-
cnt5 += 1
292-
x //= 5
293-
c = cnt2 = cnt5 = min(cnt2, cnt5)
294-
pre = suf = 1
295-
gt = False
296-
for x in range(left, right + 1):
297-
suf *= x
298-
while cnt2 and suf % 2 == 0:
299-
suf //= 2
300-
cnt2 -= 1
301-
while cnt5 and suf % 5 == 0:
302-
suf //= 5
303-
cnt5 -= 1
304-
if suf >= 1e10:
305-
gt = True
306-
suf %= int(1e10)
307-
pre *= x
308-
while pre > 1e5:
309-
pre /= 10
310-
if gt:
311-
return str(int(pre)) + "..." + str(suf % int(1e5)).zfill(5) + 'e' + str(c)
312-
return str(suf) + "e" + str(c)
313-
```
314-
315-
<!-- tabs:end -->
316-
317-
<!-- solution:end -->
318-
319271
<!-- problem:end -->

‎solution/2100-2199/2117.Abbreviating the Product of a Range/README_EN.md

+17-65
Original file line numberDiff line numberDiff line change
@@ -95,39 +95,36 @@ Hence, the abbreviated product is &quot;399168e2&quot;.
9595
#### Python3
9696

9797
```python
98-
import numpy
99-
100-
10198
class Solution:
10299
def abbreviateProduct(self, left: int, right: int) -> str:
103100
cnt2 = cnt5 = 0
104-
z = numpy.float128(0)
105101
for x in range(left, right + 1):
106-
z += numpy.log10(x)
107102
while x % 2 == 0:
108-
x //= 2
109103
cnt2 += 1
104+
x //= 2
110105
while x % 5 == 0:
111-
x //= 5
112106
cnt5 += 1
107+
x //= 5
113108
c = cnt2 = cnt5 = min(cnt2, cnt5)
114-
suf = y = 1
109+
pre = suf = 1
115110
gt = False
116111
for x in range(left, right + 1):
117-
while cnt2 and x % 2 == 0:
118-
x //= 2
112+
suf *= x
113+
while cnt2 and suf % 2 == 0:
114+
suf //= 2
119115
cnt2 -= 1
120-
while cnt5 and x % 5 == 0:
121-
x //= 5
116+
while cnt5 and suf % 5 == 0:
117+
suf //= 5
122118
cnt5 -= 1
123-
suf = suf * x % 100000
124-
if not gt:
125-
y *= x
126-
gt = y >= 1e10
127-
if not gt:
128-
return str(y) + "e" + str(c)
129-
pre = int(pow(10, z - int(z) + 4))
130-
return str(pre) + "..." + str(suf).zfill(5) + "e" + str(c)
119+
if suf >= 1e10:
120+
gt = True
121+
suf %= int(1e10)
122+
pre *= x
123+
while pre > 1e5:
124+
pre /= 10
125+
if gt:
126+
return str(int(pre)) + "..." + str(suf % int(1e5)).zfill(5) + "e" + str(c)
127+
return str(suf) + "e" + str(c)
131128
```
132129

133130
#### Java
@@ -268,49 +265,4 @@ func abbreviateProduct(left int, right int) string {
268265

269266
<!-- solution:end -->
270267

271-
<!-- solution:start -->
272-
273-
### Solution 2
274-
275-
<!-- tabs:start -->
276-
277-
#### Python3
278-
279-
```python
280-
class Solution:
281-
def abbreviateProduct(self, left: int, right: int) -> str:
282-
cnt2 = cnt5 = 0
283-
for x in range(left, right + 1):
284-
while x % 2 == 0:
285-
cnt2 += 1
286-
x //= 2
287-
while x % 5 == 0:
288-
cnt5 += 1
289-
x //= 5
290-
c = cnt2 = cnt5 = min(cnt2, cnt5)
291-
pre = suf = 1
292-
gt = False
293-
for x in range(left, right + 1):
294-
suf *= x
295-
while cnt2 and suf % 2 == 0:
296-
suf //= 2
297-
cnt2 -= 1
298-
while cnt5 and suf % 5 == 0:
299-
suf //= 5
300-
cnt5 -= 1
301-
if suf >= 1e10:
302-
gt = True
303-
suf %= int(1e10)
304-
pre *= x
305-
while pre > 1e5:
306-
pre /= 10
307-
if gt:
308-
return str(int(pre)) + "..." + str(suf % int(1e5)).zfill(5) + 'e' + str(c)
309-
return str(suf) + "e" + str(c)
310-
```
311-
312-
<!-- tabs:end -->
313-
314-
<!-- solution:end -->
315-
316268
<!-- problem:end -->

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