添加预判断长度的代码

在magazine中字符存入数组前，预先判断ransomNote和magazine的相对长度，进行处理。

problems/0383.赎金信.md

@@ -84,6 +84,10 @@ class Solution {
 public:
     bool canConstruct(string ransomNote, string magazine) {
         int record[26] = {0};
+        //add
+        if (ransomNote.size() > magazine.size()) {
+            return false;
+        }
         for (int i = 0; i < magazine.length(); i++) {
             // 通过recode数据记录 magazine里各个字符出现次数
             record[magazine[i]-'a'] ++;