Update README.md

Author: yanglbme

solution/0400-0499/0416.Partition Equal Subset Sum/README.md

@@ -193,36 +193,24 @@ function canPartition(nums: number[]): boolean {
 
 ```rust
 impl Solution {
-    #[allow(dead_code)]
     pub fn can_partition(nums: Vec<i32>) -> bool {
-        let mut sum = 0;
-        for e in &nums {
-            sum += *e;
-        }
-
-        if sum % 2 != 0 {
+        let s: i32 = nums.iter().sum();
+        if s % 2 != 0 {
             return false;
         }
-
+        let m = (s / 2) as usize;
         let n = nums.len();
-        let m = (sum / 2) as usize;
-        let mut dp: Vec<Vec<bool>> = vec![vec![false; m + 1]; n + 1];
-
-        // Initialize the dp vector
-        dp[0][0] = true;
-
-        // Begin the actual dp process
+        let mut f = vec![vec![false; m + 1]; n + 1];
+        f[0][0] = true;
+        
         for i in 1..=n {
+            let x = nums[i - 1] as usize;
             for j in 0..=m {
-                dp[i][j] = if (nums[i - 1] as usize) > j {
-                    dp[i - 1][j]
-                } else {
-                    dp[i - 1][j] || dp[i - 1][j - (nums[i - 1] as usize)]
-                };
+                f[i][j] = f[i - 1][j] || (j >= x && f[i - 1][j - x]);
             }
         }
-
-        dp[n][m]
+        
+        f[n][m]
     }
 }
 ```