1462. Course Schedule IV

class Solution {
public:
    vector<int> g[101];
    int possible[101][101],vis[101];
    void dfs(int node,int p) {
        possible[p][node] = 1;
        vis[node] = 1;
        for(int ch : g[node]) {
            if(vis[ch] == 0) dfs(ch,p);
        }
    }

    vector<bool> checkIfPrerequisite(int numCourses, vector<vector<int>>& prerequisites, vector<vector<int>>& queries) {
        memset(possible,0,sizeof possible);
        
        for(auto it : prerequisites) {
            g[it[0]].push_back(it[1]);
            
        }
        for(int i = 0; i < numCourses; i++) {
            memset(vis,0,sizeof vis);
            dfs(i,i);
        }
        

        vector<bool> ans;
        for(auto it : queries) {
            if(possible[it[0]][it[1]]) ans.push_back(true);
            else ans.push_back(false);
        }
        return ans;
    }
};