E

#include <iostream>
#include <vector>

int main() {
    int c = 0;
    int a;
    std::cin>>a;
    int map[a][a];

    std::vector<std::pair<int, int>> pairs;

    for (int x = 0; x < a; x++)
        for (int y = 0; y < a; y++)
            std::cin>>map[x][y];


    for (int x = 0; x < a; x++)
        for (int y = 0; y < x; y++)
            if (map[x][y])
                pairs.push_back(std::pair<int,int>(y+1, x+1));


    for (int x = 0; x < pairs.size(); x++)
        std::cout<<pairs[x].first << " " << pairs[x].second << std::endl;

    return 0;
}