feat: add rust solution to lc problem: No.1048 (#1727)

Author: xzhseh

solution/1000-1099/1048.Longest String Chain/README.md

@@ -184,6 +184,46 @@ public:
 };
 ```
 
+### **Rust**
+
+```rust
+use std::collections::HashMap;
+
+impl Solution {
+    #[allow(dead_code)]
+    pub fn longest_str_chain(words: Vec<String>) -> i32 {
+        let mut words = words;
+        let mut ret = 0;
+        let mut map: HashMap<String, i32> = HashMap::new();
+
+        // Sort the words vector first
+        words.sort_by(|lhs, rhs| {
+            lhs.len().cmp(&rhs.len())
+        });
+
+        // Begin the "dp" process
+        for w in words.iter() {
+            let n = w.len();
+            let mut x = 1;
+
+            for i in 0..n {
+                let s = w[..i].to_string() + &w[i + 1..];
+                let v = map
+                    .entry(s.clone())
+                    .or_default();
+                x = std::cmp::max(x, *v + 1);
+            }
+
+            map.insert(w.clone(), x);
+
+            ret = std::cmp::max(ret, x);
+        }
+
+        ret
+    }
+}
+```
+
 ### **Go**
 
 哈希表：

solution/1000-1099/1048.Longest String Chain/README_EN.md

@@ -165,6 +165,46 @@ public:
 };
 ```
 
+### **Rust**
+
+```rust
+use std::collections::HashMap;
+
+impl Solution {
+    #[allow(dead_code)]
+    pub fn longest_str_chain(words: Vec<String>) -> i32 {
+        let mut words = words;
+        let mut ret = 0;
+        let mut map: HashMap<String, i32> = HashMap::new();
+
+        // Sort the words vector first
+        words.sort_by(|lhs, rhs| {
+            lhs.len().cmp(&rhs.len())
+        });
+
+        // Begin the "dp" process
+        for w in words.iter() {
+            let n = w.len();
+            let mut x = 1;
+
+            for i in 0..n {
+                let s = w[..i].to_string() + &w[i + 1..];
+                let v = map
+                    .entry(s.clone())
+                    .or_default();
+                x = std::cmp::max(x, *v + 1);
+            }
+
+            map.insert(w.clone(), x);
+
+            ret = std::cmp::max(ret, x);
+        }
+
+        ret
+    }
+}
+```
+
 ### **Go**
 
 ```go

solution/1000-1099/1048.Longest String Chain/Solution.rs

@@ -0,0 +1,35 @@
+use std::collections::HashMap;
+
+impl Solution {
+    #[allow(dead_code)]
+    pub fn longest_str_chain(words: Vec<String>) -> i32 {
+        let mut words = words;
+        let mut ret = 0;
+        let mut map: HashMap<String, i32> = HashMap::new();
+
+        // Sort the words vector first
+        words.sort_by(|lhs, rhs| {
+            lhs.len().cmp(&rhs.len())
+        });
+
+        // Begin the "dp" process
+        for w in words.iter() {
+            let n = w.len();
+            let mut x = 1;
+
+            for i in 0..n {
+                let s = w[..i].to_string() + &w[i + 1..];
+                let v = map
+                    .entry(s.clone())
+                    .or_default();
+                x = std::cmp::max(x, *v + 1);
+            }
+
+            map.insert(w.clone(), x);
+
+            ret = std::cmp::max(ret, x);
+        }
+
+        ret
+    }
+}