feat: update solutions to lc problem: No.0006 (#4478)

No.0006.Zigzag Conversion

Author: yanglbme

solution/0000-0099/0006.Zigzag Conversion/README.md

@@ -78,9 +78,9 @@ P     I
 
 ### 方法一：模拟
 
-我们用一个二维数组 $g$ 来模拟 $Z$ 字形排列的过程，其中 $g[i][j]$ 表示第 $i$ 行第 $j$ 列的字符。初始时 $i=0$，另外我们定义一个方向变量 $k$，初始时 $k=-1$，表示向上走。
+我们用一个二维数组 $g$ 来模拟 Z 字形排列的过程，其中 $g[i][j]$ 表示第 $i$ 行第 $j$ 列的字符。初始时 $i = 0$，另外我们定义一个方向变量 $k$，初始时 $k = -1$，表示向上走。
 
-我们从左到右遍历字符串 $s$，每次遍历到一个字符 $c$，将其追加到 $g[i]$ 中，如果此时 $i=0$ 或者 $i=numRows-1$，说明当前字符位于 $Z$ 字形排列的拐点，我们将 $k$ 的值反转，即 $k=-k$。接下来，我们将 $i$ 的值更新为 $i+k$，即向上或向下移动一行。继续遍历下一个字符，直到遍历完字符串 $s$，我们返回 $g$ 中所有行拼接后的字符串即可。
+我们从左到右遍历字符串 $s$，每次遍历到一个字符 $c$，将其追加到 $g[i]$ 中。如果此时 $i = 0$ 或者 $i = \textit{numRows} - 1$，说明当前字符位于 Z 字形排列的拐点，我们将 $k$ 的值反转，即 $k = -k$。接下来，我们将 $i$ 的值更新为 $i + k$，即向上或向下移动一行。继续遍历下一个字符，直到遍历完字符串 $s$，我们返回 $g$ 中所有行拼接后的字符串即可。
 
 时间复杂度 $O(n)$，空间复杂度 $O(n)$。其中 $n$ 为字符串 $s$ 的长度。
 
@@ -199,29 +199,24 @@ function convert(s: string, numRows: number): string {
 ```rust
 impl Solution {
     pub fn convert(s: String, num_rows: i32) -> String {
-        let num_rows = num_rows as usize;
         if num_rows == 1 {
             return s;
         }
-        let mut ss = vec![String::new(); num_rows];
+
+        let num_rows = num_rows as usize;
+        let mut g = vec![String::new(); num_rows];
         let mut i = 0;
-        let mut to_down = true;
+        let mut k = -1;
+
         for c in s.chars() {
-            ss[i].push(c);
-            if to_down {
-                i += 1;
-            } else {
-                i -= 1;
-            }
+            g[i].push(c);
             if i == 0 || i == num_rows - 1 {
-                to_down = !to_down;
+                k = -k;
             }
+            i = (i as isize + k) as usize;
         }
-        let mut res = String::new();
-        for i in 0..num_rows {
-            res += &ss[i];
-        }
-        res
+
+        g.concat()
     }
 }
 ```
@@ -323,220 +318,42 @@ char* convert(char* s, int numRows) {
 }
 ```
 
-<!-- tabs:end -->
-
-<!-- solution:end -->
-
-<!-- solution:start -->
-
-### 方法二
-
-<!-- tabs:start -->
-
-#### Python3
-
-```python
-class Solution:
-    def convert(self, s: str, numRows: int) -> str:
-        if numRows == 1:
-            return s
-        group = 2 * numRows - 2
-        ans = []
-        for i in range(1, numRows + 1):
-            interval = group if i == numRows else 2 * numRows - 2 * i
-            idx = i - 1
-            while idx < len(s):
-                ans.append(s[idx])
-                idx += interval
-                interval = group - interval
-                if interval == 0:
-                    interval = group
-        return ''.join(ans)
-```
-
-#### Java
-
-```java
-class Solution {
-    public String convert(String s, int numRows) {
-        if (numRows == 1) {
-            return s;
-        }
-        StringBuilder ans = new StringBuilder();
-        int group = 2 * numRows - 2;
-        for (int i = 1; i <= numRows; i++) {
-            int interval = i == numRows ? group : 2 * numRows - 2 * i;
-            int idx = i - 1;
-            while (idx < s.length()) {
-                ans.append(s.charAt(idx));
-                idx += interval;
-                interval = group - interval;
-                if (interval == 0) {
-                    interval = group;
-                }
-            }
-        }
-        return ans.toString();
-    }
-}
-```
-
-#### C++
-
-```cpp
-class Solution {
-public:
-    string convert(string s, int numRows) {
-        if (numRows == 1) return s;
-        string ans;
-        int group = 2 * numRows - 2;
-        for (int i = 1; i <= numRows; ++i) {
-            int interval = i == numRows ? group : 2 * numRows - 2 * i;
-            int idx = i - 1;
-            while (idx < s.length()) {
-                ans.push_back(s[idx]);
-                idx += interval;
-                interval = group - interval;
-                if (interval == 0) interval = group;
-            }
-        }
-        return ans;
-    }
-};
-```
-
-#### Go
-
-```go
-func convert(s string, numRows int) string {
-	if numRows == 1 {
-		return s
-	}
-	n := len(s)
-	ans := make([]byte, n)
-	step := 2*numRows - 2
-	count := 0
-	for i := 0; i < numRows; i++ {
-		for j := 0; j+i < n; j += step {
-			ans[count] = s[i+j]
-			count++
-			if i != 0 && i != numRows-1 && j+step-i < n {
-				ans[count] = s[j+step-i]
-				count++
-			}
-		}
-	}
-	return string(ans)
-}
-```
-
-#### TypeScript
-
-```ts
-function convert(s: string, numRows: number): string {
-    if (numRows === 1) {
-        return s;
-    }
-    const ss = new Array(numRows).fill('');
-    let i = 0;
-    let toDown = true;
-    for (const c of s) {
-        ss[i] += c;
-        if (toDown) {
-            i++;
-        } else {
-            i--;
-        }
-        if (i === 0 || i === numRows - 1) {
-            toDown = !toDown;
-        }
-    }
-    return ss.reduce((r, s) => r + s);
-}
-```
-
-#### Rust
-
-```rust
-impl Solution {
-    pub fn convert(s: String, num_rows: i32) -> String {
-        let num_rows = num_rows as usize;
-        let mut rows = vec![String::new(); num_rows];
-        let iter = (0..num_rows).chain((1..num_rows - 1).rev()).cycle();
-        iter.zip(s.chars()).for_each(|(i, c)| rows[i].push(c));
-        rows.into_iter().collect()
-    }
-}
-```
-
-#### JavaScript
-
-```js
-/**
- * @param {string} s
- * @param {number} numRows
- * @return {string}
- */
-var convert = function (s, numRows) {
-    if (numRows == 1) return s;
-    const arr = new Array(numRows);
-    for (let i = 0; i < numRows; i++) arr[i] = [];
-    let mi = 0,
-        isDown = true;
-    for (const c of s) {
-        arr[mi].push(c);
-
-        if (mi >= numRows - 1) isDown = false;
-        else if (mi <= 0) isDown = true;
-
-        if (isDown) mi++;
-        else mi--;
-    }
-    let ans = [];
-    for (const item of arr) {
-        ans = ans.concat(item);
-    }
-    return ans.join('');
-};
-```
-
 #### PHP
 
 ```php
 class Solution {
     /**
-     * @param string $s
-     * @param int $numRows
-     * @return string
+     * @param String $s
+     * @param Integer $numRows
+     * @return String
      */
-
     function convert($s, $numRows) {
-        if ($numRows == 1 || strlen($s) <= $numRows) {
+        if ($numRows == 1) {
             return $s;
         }
 
-        $result = '';
-        $cycleLength = 2 * $numRows - 2;
-        $n = strlen($s);
+        $g = array_fill(0, $numRows, '');
+        $i = 0;
+        $k = -1;
 
-        for ($i = 0; $i < $numRows; $i++) {
-            for ($j = 0; $j + $i < $n; $j += $cycleLength) {
-                $result .= $s[$j + $i];
+        $length = strlen($s);
+        for ($j = 0; $j < $length; $j++) {
+            $c = $s[$j];
+            $g[$i] .= $c;
 
-                if ($i != 0 && $i != $numRows - 1 && $j + $cycleLength - $i < $n) {
-                    $result .= $s[$j + $cycleLength - $i];
-                }
+            if ($i == 0 || $i == $numRows - 1) {
+                $k = -$k;
             }
-        }
 
-        return $result;
+            $i += $k;
+        }
+        return implode('', $g);
     }
 }
-``
+```
 
 <!-- tabs:end -->
 
 <!-- solution:end -->
 
 <!-- problem:end -->
-```