View Compilation Error

0_0_37751417_19168.cpp: In function 'void calc(int, int)':
0_0_37751417_19168.cpp:14:50: error: 'struct std::pair<int, int>' has no member named 'fi'
  for(int i=n;i;i--)for(auto j:gr[i])bs[i]|=(bs[j.fi]&qr[j.se]);
                                                  ^
0_0_37751417_19168.cpp:14:59: error: 'struct std::pair<int, int>' has no member named 'se'
  for(int i=n;i;i--)for(auto j:gr[i])bs[i]|=(bs[j.fi]&qr[j.se]);
                                                           ^