feat: add solutions to lc problems: No.3503,3504 (#4313)

* No.3503.Longest Palindrome After Substring Concatenation I
* No.3504.Longest Palindrome After Substring Concatenation II

Author: yanglbme

solution/3500-3599/3503.Longest Palindrome After Substring Concatenation I/README.md

@@ -96,25 +96,222 @@ edit_url: https://github.com/doocs/leetcode/edit/main/solution/3500-3599/3503.Lo
 #### Python3
 
 ```python
-
+class Solution:
+    def longestPalindrome(self, s: str, t: str) -> int:
+        def expand(s: str, g: List[int], l: int, r: int):
+            while l >= 0 and r < len(s) and s[l] == s[r]:
+                g[l] = max(g[l], r - l + 1)
+                l, r = l - 1, r + 1
+
+        def calc(s: str) -> List[int]:
+            n = len(s)
+            g = [0] * n
+            for i in range(n):
+                expand(s, g, i, i)
+                expand(s, g, i, i + 1)
+            return g
+
+        m, n = len(s), len(t)
+        t = t[::-1]
+        g1, g2 = calc(s), calc(t)
+        ans = max(*g1, *g2)
+        f = [[0] * (n + 1) for _ in range(m + 1)]
+        for i, a in enumerate(s, 1):
+            for j, b in enumerate(t, 1):
+                if a == b:
+                    f[i][j] = f[i - 1][j - 1] + 1
+                    ans = max(ans, f[i][j] * 2 + (0 if i >= m else g1[i]))
+                    ans = max(ans, f[i][j] * 2 + (0 if j >= n else g2[j]))
+        return ans
 ```
 
 #### Java
 
 ```java
-
+class Solution {
+    public int longestPalindrome(String S, String T) {
+        char[] s = S.toCharArray();
+        char[] t = new StringBuilder(T).reverse().toString().toCharArray();
+        int m = s.length, n = t.length;
+        int[] g1 = calc(s), g2 = calc(t);
+        int ans = Math.max(Arrays.stream(g1).max().getAsInt(), Arrays.stream(g2).max().getAsInt());
+        int[][] f = new int[m + 1][n + 1];
+        for (int i = 1; i <= m; ++i) {
+            for (int j = 1; j <= n; ++j) {
+                if (s[i - 1] == t[j - 1]) {
+                    f[i][j] = f[i - 1][j - 1] + 1;
+                    ans = Math.max(ans, f[i][j] * 2 + (i < m ? g1[i] : 0));
+                    ans = Math.max(ans, f[i][j] * 2 + (j < n ? g2[j] : 0));
+                }
+            }
+        }
+        return ans;
+    }
+
+    private void expand(char[] s, int[] g, int l, int r) {
+        while (l >= 0 && r < s.length && s[l] == s[r]) {
+            g[l] = Math.max(g[l], r - l + 1);
+            --l;
+            ++r;
+        }
+    }
+
+    private int[] calc(char[] s) {
+        int n = s.length;
+        int[] g = new int[n];
+        for (int i = 0; i < n; ++i) {
+            expand(s, g, i, i);
+            expand(s, g, i, i + 1);
+        }
+        return g;
+    }
+}
 ```
 
 #### C++
 
 ```cpp
-
+class Solution {
+public:
+    int longestPalindrome(string s, string t) {
+        int m = s.size(), n = t.size();
+        ranges::reverse(t);
+        vector<int> g1 = calc(s), g2 = calc(t);
+        int ans = max(ranges::max(g1), ranges::max(g2));
+        vector<vector<int>> f(m + 1, vector<int>(n + 1));
+        for (int i = 1; i <= m; ++i) {
+            for (int j = 1; j <= n; ++j) {
+                if (s[i - 1] == t[j - 1]) {
+                    f[i][j] = f[i - 1][j - 1] + 1;
+                    ans = max(ans, f[i][j] * 2 + (i < m ? g1[i] : 0));
+                    ans = max(ans, f[i][j] * 2 + (j < n ? g2[j] : 0));
+                }
+            }
+        }
+        return ans;
+    }
+
+private:
+    void expand(const string& s, vector<int>& g, int l, int r) {
+        while (l >= 0 && r < s.size() && s[l] == s[r]) {
+            g[l] = max(g[l], r - l + 1);
+            --l;
+            ++r;
+        }
+    }
+
+    vector<int> calc(const string& s) {
+        int n = s.size();
+        vector<int> g(n, 0);
+        for (int i = 0; i < n; ++i) {
+            expand(s, g, i, i);
+            expand(s, g, i, i + 1);
+        }
+        return g;
+    }
+};
 ```
 
 #### Go
 
 ```go
+func longestPalindrome(s, t string) int {
+	m, n := len(s), len(t)
+	t = reverse(t)
+
+	g1, g2 := calc(s), calc(t)
+	ans := max(slices.Max(g1), slices.Max(g2))
+
+	f := make([][]int, m+1)
+	for i := range f {
+		f[i] = make([]int, n+1)
+	}
+
+	for i := 1; i <= m; i++ {
+		for j := 1; j <= n; j++ {
+			if s[i-1] == t[j-1] {
+				f[i][j] = f[i-1][j-1] + 1
+				a, b := 0, 0
+				if i < m {
+					a = g1[i]
+				}
+				if j < n {
+					b = g2[j]
+				}
+				ans = max(ans, f[i][j]*2+a)
+				ans = max(ans, f[i][j]*2+b)
+			}
+		}
+	}
+	return ans
+}
+
+func calc(s string) []int {
+	n, g := len(s), make([]int, len(s))
+	for i := 0; i < n; i++ {
+		expand(s, g, i, i)
+		expand(s, g, i, i+1)
+	}
+	return g
+}
+
+func expand(s string, g []int, l, r int) {
+	for l >= 0 && r < len(s) && s[l] == s[r] {
+		g[l] = max(g[l], r-l+1)
+		l, r = l-1, r+1
+	}
+}
+
+func reverse(s string) string {
+	r := []rune(s)
+	slices.Reverse(r)
+	return string(r)
+}
+```
 
+#### TypeScript
+
+```ts
+function longestPalindrome(s: string, t: string): number {
+    function expand(s: string, g: number[], l: number, r: number): void {
+        while (l >= 0 && r < s.length && s[l] === s[r]) {
+            g[l] = Math.max(g[l], r - l + 1);
+            l--;
+            r++;
+        }
+    }
+
+    function calc(s: string): number[] {
+        const n = s.length;
+        const g: number[] = Array(n).fill(0);
+        for (let i = 0; i < n; i++) {
+            expand(s, g, i, i);
+            expand(s, g, i, i + 1);
+        }
+        return g;
+    }
+
+    const m = s.length,
+        n = t.length;
+    t = t.split('').reverse().join('');
+    const g1 = calc(s);
+    const g2 = calc(t);
+    let ans = Math.max(...g1, ...g2);
+
+    const f: number[][] = Array.from({ length: m + 1 }, () => Array(n + 1).fill(0));
+
+    for (let i = 1; i <= m; i++) {
+        for (let j = 1; j <= n; j++) {
+            if (s[i - 1] === t[j - 1]) {
+                f[i][j] = f[i - 1][j - 1] + 1;
+                ans = Math.max(ans, f[i][j] * 2 + (i >= m ? 0 : g1[i]));
+                ans = Math.max(ans, f[i][j] * 2 + (j >= n ? 0 : g2[j]));
+            }
+        }
+    }
+
+    return ans;
+}
 ```
 
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