Update Solution.swift

Author: yanglbme

lcof2/剑指 Offer II 104. 排列的数目/Solution.swift

@@ -1,16 +1,16 @@
 class Solution {
     func combinationSum4(_ nums: [Int], _ target: Int) -> Int {
         var dp = [Int](repeating: 0, count: target + 1)
-        dp[0] = 1 
+        dp[0] = 1
 
         for i in 1...target {
             for num in nums {
-                if i >= num {
+                if i >= num, dp[i] <= Int.max - dp[i - num] {
                     dp[i] += dp[i - num]
                 }
             }
         }
-        
+
         return dp[target]
     }
-}
+}