Interleaving String

Desicription

Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2.

For example,
Given:
s1 = "aabcc",
s2 = "dbbca",

When s3 = "aadbbcbcac", return true.
When s3 = "aadbbbaccc", return false.

Solution

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class Solution {
public:
    bool isInterleave(string s1, string s2, string s3) {
        if(s1.size() + s2.size() != s3.size())
            return 0;
        vector<vector<bool>> table(s1.size()+1, vector<bool>(s2.size()+1, 0));
        for(int i = 0; i <= s1.size(); i++) {
            for(int j = 0; j <= s2.size(); j++){
                if(!i && !j)
                    table[i][j] = 1;
                else if(!i)
                    table[i][j] = (table[i][j-1] && s2[j-1] == s3[i+j-1]);
                else if(!j)
                    table[i][j] = (table[i-1][j] && s1[i-1] == s3[i+j-1]);
                else
                    table[i][j] = ((table[i-1][j] && s1[i-1] == s3[i+j-1]) || (table[i][j-1] && s2[j-1] == s3[i+j-1]));
            }
        }
        return table[s1.size()][s2.size()];
    }
};