算法leetcode|44. 通配符匹配(rust重拳出击)



44. 通配符匹配:

给定一个字符串 (s) 和一个字符模式 (p) ,实现一个支持 '?''*' 的通配符匹配。

'?' 可以匹配任何单个字符。
'*' 可以匹配任意字符串(包括空字符串)。

两个字符串完全匹配才算匹配成功。

说明:

  • s 可能为空,且只包含从 a-z 的小写字母。
  • p 可能为空,且只包含从 a-z 的小写字母,以及字符 ?*

样例 1:

输入:
	s = "aa"
	p = "a"
	
输出: 
	false
	
解释: 
	"a" 无法匹配 "aa" 整个字符串。

样例 2:

输入:
	s = "aa"
	p = "*"
	
输出: 
	true
	
解释: 
	'*' 可以匹配任意字符串。

样例 3:

输入:
	s = "cb"
	p = "?a"
	
输出: 
	false
	
解释: 
	'?' 可以匹配 'c', 但第二个 'a' 无法匹配 'b'。

样例 4:

输入:
	s = "adceb"
	p = "*a*b"
	
输出: 
	true
	
解释: 
	第一个 '*' 可以匹配空字符串, 第二个 '*' 可以匹配字符串 "dce".

样例 5:

输入:
	s = "acdcb"
	p = "a*c?b"

输出: 
	false

分析:

  • 面对这道算法题目,二当家的陷入了沉思。
  • 主要是星号匹配的处理,整体去看,比较迷茫,必须要分解问题,可以考虑动态规划。
  • 在模式字符串中出现的字符和问号可以理解为是固定匹配的,而星号则需要暴力尝试,所以我们可以考虑把模式串按照星号分割,然后贪心的去尝试匹配字符和问号。

题解:

rust

impl Solution {
    
    
    pub fn is_match(s: String, p: String) -> bool {
    
    
        fn is_all_stars(bs: &[u8], left: usize, right: usize) -> bool {
    
    
            for i in left..right {
    
    
                if bs[i] != b'*' {
    
    
                    return false;
                }
            }
            return true;
        }
        fn is_char_match(u: u8, v: u8) -> bool {
    
    
            u == v || v == b'?'
        }

        let sbs = s.as_bytes();
        let pbs = p.as_bytes();
        let (mut s_right, mut p_right) = (s.len(), p.len());
        while s_right > 0 && p_right > 0 && pbs[p_right - 1] != b'*' {
    
    
            if is_char_match(sbs[s_right - 1], pbs[p_right - 1]) {
    
    
                s_right -= 1;
                p_right -= 1;
            } else {
    
    
                return false;
            }
        }

        if p_right == 0 {
    
    
            return s_right == 0;
        }

        let (mut s_index, mut p_index) = (0, 0);
        let (mut s_record, mut p_record) = (-1i32, -1i32);

        while s_index < s_right && p_index < p_right {
    
    
            if pbs[p_index] == b'*' {
    
    
                p_index += 1;
                s_record = s_index as i32;
                p_record = p_index as i32;
            } else if is_char_match(sbs[s_index], pbs[p_index]) {
    
    
                s_index += 1;
                p_index += 1;
            } else if s_record != -1 && s_record + 1 < s_right as i32 {
    
    
                s_record += 1;
                s_index = s_record as usize;
                p_index = p_record as usize;
            } else {
    
    
                return false;
            }
        }

        return is_all_stars(pbs, p_index, p_right);
    }
}

go

func isMatch(s string, p string) bool {
    
    
    charMatch := func(u, v byte) bool {
    
    
		return u == v || v == '?'
	}
	allStars := func(str string, left, right int) bool {
    
    
		for i := left; i < right; i++ {
    
    
			if str[i] != '*' {
    
    
				return false
			}
		}
		return true
	}

	for len(s) > 0 && len(p) > 0 && p[len(p)-1] != '*' {
    
    
		if charMatch(s[len(s)-1], p[len(p)-1]) {
    
    
			s = s[:len(s)-1]
			p = p[:len(p)-1]
		} else {
    
    
			return false
		}
	}
	if len(p) == 0 {
    
    
		return len(s) == 0
	}
	sIndex, pIndex := 0, 0
	sRecord, pRecord := -1, -1
	for sIndex < len(s) && pRecord < len(p) {
    
    
		if p[pIndex] == '*' {
    
    
			pIndex++
			sRecord, pRecord = sIndex, pIndex
		} else if charMatch(s[sIndex], p[pIndex]) {
    
    
			sIndex++
			pIndex++
		} else if sRecord != -1 && sRecord+1 < len(s) {
    
    
			sRecord++
			sIndex, pIndex = sRecord, pRecord
		} else {
    
    
			return false
		}
	}
	return allStars(p, pIndex, len(p))
}

c++

class Solution {
    
    
public:
    bool isMatch(string s, string p) {
    
    
        auto allStars = [](const string &str, int left, int right) {
    
    
            for (int i = left; i < right; ++i) {
    
    
                if (str[i] != '*') {
    
    
                    return false;
                }
            }
            return true;
        };
        auto charMatch = [](char u, char v) {
    
    
            return u == v || v == '?';
        };

        while (s.size() && p.size() && p.back() != '*') {
    
    
            if (charMatch(s.back(), p.back())) {
    
    
                s.pop_back();
                p.pop_back();
            } else {
    
    
                return false;
            }
        }
        if (p.empty()) {
    
    
            return s.empty();
        }

        int sIndex = 0, pIndex = 0;
        int sRecord = -1, pRecord = -1;
        while (sIndex < s.size() && pIndex < p.size()) {
    
    
            if (p[pIndex] == '*') {
    
    
                ++pIndex;
                sRecord = sIndex;
                pRecord = pIndex;
            } else if (charMatch(s[sIndex], p[pIndex])) {
    
    
                ++sIndex;
                ++pIndex;
            } else if (sRecord != -1 && sRecord + 1 < s.size()) {
    
    
                ++sRecord;
                sIndex = sRecord;
                pIndex = pRecord;
            } else {
    
    
                return false;
            }
        }
        return allStars(p, pIndex, p.size());
    }
};

c

bool allStars(char *str, int left, int right) {
    
    
    for (int i = left; i < right; ++i) {
    
    
        if (str[i] != '*') {
    
    
            return false;
        }
    }
    return true;
}

bool charMatch(char u, char v) {
    
     return u == v || v == '?'; };

bool isMatch(char *s, char *p) {
    
    
    int len_s = strlen(s), len_p = strlen(p);
    while (len_s && len_p && p[len_p - 1] != '*') {
    
    
        if (charMatch(s[len_s - 1], p[len_p - 1])) {
    
    
            len_s--;
            len_p--;
        } else {
    
    
            return false;
        }
    }
    if (len_p == 0) {
    
    
        return len_s == 0;
    }

    int sIndex = 0, pIndex = 0;
    int sRecord = -1, pRecord = -1;
    while (sIndex < len_s && pIndex < len_p) {
    
    
        if (p[pIndex] == '*') {
    
    
            ++pIndex;
            sRecord = sIndex;
            pRecord = pIndex;
        } else if (charMatch(s[sIndex], p[pIndex])) {
    
    
            ++sIndex;
            ++pIndex;
        } else if (sRecord != -1 && sRecord + 1 < len_s) {
    
    
            ++sRecord;
            sIndex = sRecord;
            pIndex = pRecord;
        } else {
    
    
            return false;
        }
    }
    return allStars(p, pIndex, len_p);
}

python

class Solution:
    def isMatch(self, s: str, p: str) -> bool:
        def is_all_stars(st: str, left: int, right: int) -> bool:
            return all(st[i] == '*' for i in range(left, right))

        def is_char_match(u: str, v: str) -> bool:
            return u == v or v == '?'

        s_right, p_right = len(s), len(p)
        while s_right > 0 and p_right > 0 and p[p_right - 1] != '*':
            if is_char_match(s[s_right - 1], p[p_right - 1]):
                s_right -= 1
                p_right -= 1
            else:
                return False

        if p_right == 0:
            return s_right == 0

        s_index, p_index = 0, 0
        s_record, p_record = -1, -1
        while s_index < s_right and p_index < p_right:
            if p[p_index] == '*':
                p_index += 1
                s_record, p_record = s_index, p_index
            elif is_char_match(s[s_index], p[p_index]):
                s_index += 1
                p_index += 1
            elif s_record != -1 and s_record + 1 < s_right:
                s_record += 1
                s_index, p_index = s_record, p_record
            else:
                return False

        return is_all_stars(p, p_index, p_right)


java

class Solution {
    
    
    public boolean isMatch(String s, String p) {
    
    
        int sRight = s.length(), pRight = p.length();
        while (sRight > 0 && pRight > 0 && p.charAt(pRight - 1) != '*') {
    
    
            if (charMatch(s.charAt(sRight - 1), p.charAt(pRight - 1))) {
    
    
                --sRight;
                --pRight;
            } else {
    
    
                return false;
            }
        }

        if (pRight == 0) {
    
    
            return sRight == 0;
        }

        int sIndex = 0, pIndex = 0;
        int sRecord = -1, pRecord = -1;
        
        while (sIndex < sRight && pIndex < pRight) {
    
    
            if (p.charAt(pIndex) == '*') {
    
    
                ++pIndex;
                sRecord = sIndex;
                pRecord = pIndex;
            } else if (charMatch(s.charAt(sIndex), p.charAt(pIndex))) {
    
    
                ++sIndex;
                ++pIndex;
            } else if (sRecord != -1 && sRecord + 1 < sRight) {
    
    
                ++sRecord;
                sIndex = sRecord;
                pIndex = pRecord;
            } else {
    
    
                return false;
            }
        }

        return allStars(p, pIndex, pRight);
    }

    public boolean allStars(String str, int left, int right) {
    
    
        for (int i = left; i < right; ++i) {
    
    
            if (str.charAt(i) != '*') {
    
    
                return false;
            }
        }
        return true;
    }

    public boolean charMatch(char u, char v) {
    
    
        return u == v || v == '?';
    }
}

非常感谢你阅读本文~
欢迎【点赞】【收藏】【评论】~
放弃不难,但坚持一定很酷~
希望我们大家都能每天进步一点点~
本文由 二当家的白帽子:https://le-yi.blog.csdn.net/ 博客原创~


猜你喜欢

转载自blog.csdn.net/leyi520/article/details/129926308