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#include <iostream>
#include <vector>

class Solution {
public:
    std::vector<bool> checkIfPrerequisite(int numCourses, std::vector<std::vector<int>>& prerequisites, std::vector<std::vector<int>>& queries) {
        std::vector<std::vector<bool>> d(numCourses, std::vector<bool>(numCourses, false));
        for (auto& e : prerequisites) {
            d[e[0]][e[1]] = true;
        }
        for (int k = 0; k < numCourses; ++k) {
            for (int i = 0; i < numCourses; ++i) {
                for (int j = 0; j < numCourses; ++j) {
                    if (d[i][k] && d[k][j]) {
                        d[i][j] = true;
                    }
                }
            }
        }
        
        int n = queries.size();
        std::vector<bool> res(n);
        for (int i = 0; i < n; ++i) {
            res[i] = d[queries[i][0]][queries[i][1]];
        }
        return res;
    }
};