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###### tags: `Leetcode`

# 953. Verifying an Alien Dictionary

###### Link : https://leetcode.com/problems/verifying-an-alien-dictionary/description/

## 題目
判斷所有字串有沒有按照題目給的字典序排序。
## 程式碼

class Solution {
public:
    bool isAlienSorted(vector<string>& words, string order) {
        vector<int> Order(26);
        //列出小寫英文字元的所有大小
        for(int i = 0;i < order.size();i++)
            Order[order[i] - 'a'] = i;
        for(int i = 0;i < words.size() - 1;i++)
            //如果前者比後者大，回傳false
            if(!isSorted(Order, words[i], words[i + 1]))
                return false;
        //所有都符合規則，回傳true
        return true;
    }
    bool isSorted(vector<int> &Order, string &str1, string &str2){
        for(int i = 0;i < str1.size();i++){
            //大於回傳False；小於回傳true；等於繼續跑迴圈
            if(str2[i] == '\0' || Order[str1[i]-'a'] > Order[str2[i]-'a'])
                return false;
            else if(Order[str1[i]-'a'] < Order[str2[i]-'a'])
                return true;
        }
        return true;
    }
};

## Date
### 2023/2/2