399-1

class Solution {
public:
    vector<double> calcEquation(vector<vector<string>>& equations, vector<double>& values, vector<vector<string>>& queries) {
        map<string, int> m;
        int count = 0;
        for(auto edge: equations){
            if(!m.count(edge[0]))
                m[edge[0]] = count++;
            if(!m.count(edge[1]))
                m[edge[1]] = count++;
        }
        double dp[count][count];
        for(int  i=0; i<count; i++)
            for(int j=0; j<count; j++){
                if(i == j)
                    dp[i][j] = 1.0;
                else
                    dp[i][j] = -1.0;
            }
        for(int i=0; i<equations.size(); i++){
            int x = m[equations[i][0]];
            int y = m[equations[i][1]];
            double val = values[i];
            dp[x][y] = val;
            dp[y][x] = 1.0/val;
        }

        for(int k=0; k<count; k++)
            for(int i=0; i<count; i++)
                for(int j=0; j<count; j++){
                    if(dp[i][k] != -1.0 && dp[k][j] != -1.0)
                        dp[i][j] = dp[i][k]*dp[k][j];
                }

        vector<double> ans;
        for(auto q: queries){
            if(m.count(q[0]) && m.count(q[1])){
                int x = m[q[0]];
                int y = m[q[1]];
                ans.push_back(dp[x][y]);
            }
            else
                ans.push_back(-1.0);
        }
        return ans;
    }
};