Update README.md

Author: yanglbme

lcof2/剑指 Offer II 103. 最少的硬币数目/README.md

@@ -174,16 +174,16 @@ var coinChange = function (coins, amount) {
 ```swift
 class Solution {
     func coinChange(_ coins: [Int], _ amount: Int) -> Int {
-        
         var dp = [Int](repeating: amount + 1, count: amount + 1)
         dp[0] = 0  
-        
+
         for coin in coins {
+            if coin > amount { continue }
             for j in coin...amount {
                 dp[j] = min(dp[j], dp[j - coin] + 1)
             }
         }
-        
+
         return dp[amount] > amount ? -1 : dp[amount]
     }
 }