/in/foo.cc: In function 'void solve()':
/in/foo.cc:25:12: warning: unused variable 'ans' [-Wunused-variable]
   25 |         ll ans = 1;
      |            ^~~
/in/foo.cc:26:12: warning: unused variable 'last' [-Wunused-variable]
   26 |         ll last = a[1].r;
      |            ^~~~