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1880. 检查某单词是否等于两单词之和

题目描述

字母的 字母值 取决于字母在字母表中的位置,从 0 开始 计数。即,'a' -> 0'b' -> 1'c' -> 2,以此类推。

对某个由小写字母组成的字符串 s 而言,其 数值 就等于将 s 中每个字母的 字母值 按顺序 连接转换 成对应整数。

  • 例如,s = "acb" ,依次连接每个字母的字母值可以得到 "021" ,转换为整数得到 21

给你三个字符串 firstWordsecondWordtargetWord ,每个字符串都由从 'a''j'含 'a''j' )的小写英文字母组成。

如果 firstWord secondWord数值之和 等于 targetWord 的数值,返回 true ;否则,返回 false

 

示例 1:

输入:firstWord = "acb", secondWord = "cba", targetWord = "cdb"
输出:true
解释:
firstWord 的数值为 "acb" -> "021" -> 21
secondWord 的数值为 "cba" -> "210" -> 210
targetWord 的数值为 "cdb" -> "231" -> 231
由于 21 + 210 == 231 ,返回 true

示例 2:

输入:firstWord = "aaa", secondWord = "a", targetWord = "aab"
输出:false
解释:
firstWord 的数值为 "aaa" -> "000" -> 0
secondWord 的数值为 "a" -> "0" -> 0
targetWord 的数值为 "aab" -> "001" -> 1
由于 0 + 0 != 1 ,返回 false

示例 3:

输入:firstWord = "aaa", secondWord = "a", targetWord = "aaaa"
输出:true
解释:
firstWord 的数值为 "aaa" -> "000" -> 0
secondWord 的数值为 "a" -> "0" -> 0
targetWord 的数值为 "aaaa" -> "0000" -> 0
由于 0 + 0 == 0 ,返回 true

 

提示:

  • 1 <= firstWord.length, secondWord.length, targetWord.length <= 8
  • firstWordsecondWordtargetWord 仅由从 'a''j'含 'a''j' )的小写英文字母组成

解法

方法一

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class Solution:
    def isSumEqual(self, firstWord: str, secondWord: str, targetWord: str) -> bool:
        def f(s):
            res = 0
            for c in s:
                res = res * 10 + (ord(c) - ord('a'))
            return res

        return f(firstWord) + f(secondWord) == f(targetWord)
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class Solution {
    public boolean isSumEqual(String firstWord, String secondWord, String targetWord) {
        return f(firstWord) + f(secondWord) == f(targetWord);
    }

    private int f(String s) {
        int res = 0;
        for (char c : s.toCharArray()) {
            res = res * 10 + (c - 'a');
        }
        return res;
    }
}
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class Solution {
public:
    bool isSumEqual(string firstWord, string secondWord, string targetWord) {
        return f(firstWord) + f(secondWord) == f(targetWord);
    }

    int f(string s) {
        int res = 0;
        for (char c : s) res = res * 10 + (c - 'a');
        return res;
    }
};
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func isSumEqual(firstWord string, secondWord string, targetWord string) bool {
    f := func(s string) int {
        res := 0
        for _, c := range s {
            res = res*10 + int(c-'a')
        }
        return res
    }
    return f(firstWord)+f(secondWord) == f(targetWord)
}
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function isSumEqual(firstWord: string, secondWord: string, targetWord: string): boolean {
    const calc = (s: string) => {
        let res = 0;
        for (const c of s) {
            res = res * 10 + c.charCodeAt(0) - 'a'.charCodeAt(0);
        }
        return res;
    };
    return calc(firstWord) + calc(secondWord) === calc(targetWord);
}
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impl Solution {
    fn calc(s: &String) -> i32 {
        let mut res = 0;
        for c in s.as_bytes() {
            res = res * 10 + ((c - b'a') as i32);
        }
        res
    }

    pub fn is_sum_equal(first_word: String, second_word: String, target_word: String) -> bool {
        Self::calc(&first_word) + Self::calc(&second_word) == Self::calc(&target_word)
    }
}
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/**
 * @param {string} firstWord
 * @param {string} secondWord
 * @param {string} targetWord
 * @return {boolean}
 */
var isSumEqual = function (firstWord, secondWord, targetWord) {
    function f(s) {
        let res = 0;
        for (let c of s) {
            res = res * 10 + (c.charCodeAt() - 'a'.charCodeAt());
        }
        return res;
    }
    return f(firstWord) + f(secondWord) == f(targetWord);
};
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int calc(char* s) {
    int res = 0;
    for (int i = 0; s[i]; i++) {
        res = res * 10 + s[i] - 'a';
    }
    return res;
}

bool isSumEqual(char* firstWord, char* secondWord, char* targetWord) {
    return calc(firstWord) + calc(secondWord) == calc(targetWord);
}

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