LeetCode 97. 交错字符串

LeetCode 97. 交错字符串

const int N = 110;
class Solution {
    
public:
    bool f[N][N] = {
    false}; // 是 s1 前 i 个字符和 s2 前 j 个字符能够组成 s3 前 i+j
    bool isInterleave(string s1, string s2, string s3) {
    
        int n = s1.size(), m = s2.size();
        if(n + m != s3.size()) return false;

        f[0][0] = true;
        for(int i = 1; i <= n; i ++)
            if(s1[i - 1] != s3[i - 1])
                break;
            else f[i][0] = true;
        for(int i = 1; i <= m; i ++)
            if(s2[i - 1] != s3[i - 1])
                break;
            else f[0][i] = true;
        
        for(int i = 1; i <= n; i ++)
            for(int j = 1; j <= m; j ++)
            {
    
                f[i][j] = (s1[i - 1] == s3[i + j - 1] && f[i - 1][j]) || (s2[j - 1] == s3[i + j - 1] && f[i][j - 1]); //是当前字符是s1， 或者s2
            }
        return f[n][m];
    }
};