Leetcode-Regular Expression Matching(C++)

Implement regular expression matching with support for ‘.’ and ‘*’.

‘.’ Matches any single character.
‘*’ Matches zero or more of the preceding element.

The matching should cover the entire input string (not partial).

The function prototype should be:
bool isMatch(const char *s, const char *p)

Some examples:
isMatch(“aa”,“a”) → false
isMatch(“aa”,“aa”) → true
isMatch(“aaa”,“aa”) → false
isMatch(“aa”, “a*”) → true
isMatch(“aa”, “.") → true
isMatch(“ab”, ".
”) → true
isMatch(“aab”, “cab”) → true
DP

bool isMatch(string s, string p) {
    int sl=s.length();
    int pl=p.length();
    
    vector<vector<bool>> dp(pl+1,vector<bool>(sl+1,false));
    dp[0][0]=true;
    
    for(int i=1;i<=pl;++i)
    {
        dp[i][0]=i-2>=0&&p[i-1]=='*'&&dp[i-2][0];
        for(int j=1;j<=sl;++j)
        {
            if(p[i-1]==s[j-1]||p[i-1]=='.')
            {
                dp[i][j]=dp[i-1][j-1];
            }
            else if(p[i-1]=='*'&&i-2>=0)
            {
                if(dp[i-2][j]||((p[i-2]==s[j-1]||p[i-2]=='.')&&dp[i][j-1]))
                {
                    dp[i][j]=true;
                }
                else 
                {
                    dp[i][j]=false;
                }
            }
            else
            {
                dp[i][j]=false;
            }
            
        }
        
    }
    return dp[pl][sl];

             
    }
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