10. Regular Expression Matching

动态规划 网上看的代码 以后学了再来写题解 现在一知半解

class Solution {
public:
    bool isMatch(string s, string p) {
        int m = s.size(), n = p.size();
        vector<vector<bool>>dp = { m + 1,vector<bool>(n + 1,false) };
        dp[0][0] = true;
        for (int i = 0; i <= m; ++i) {
            for (int j = 1; j <= n; ++j) {
                if (p[j - 1] == '*') {
                    dp[i][j] = dp[i][j - 2] ||
                        (i > 0 && (s[i - 1] == p[j - 2]||p[j-2]=='.') && dp[i - 1][j]);
                }
                else {
                    if (i > 0 && (s[i - 1] == p[j - 1] || p[j - 1] == '.')) {
                        dp[i][j] = dp[i - 1][j - 1];
                    }
                }
            }
        }
        return dp[m][n];
    }
};