/in/foo.cc: In function 'int solve_aux_3()':
/in/foo.cc:149:8: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
 return ans;
        ^~~
/in/foo.cc: In function 'int solve_aux_2()':
/in/foo.cc:212:8: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
 return ans;
        ^~~