foo.cc: In function ‘void del_(int)’:
foo.cc:77:17: warning: this ‘if’ clause does not guard... [-Wmisleading-indentation]
   77 |                 if (t[u].lch) qu.push(t[u].lch); if (t[u].rch) qu.push(t[u].rch);
      |                 ^~
foo.cc:77:50: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the ‘if’
   77 |                 if (t[u].lch) qu.push(t[u].lch); if (t[u].rch) qu.push(t[u].rch);
      |                                                  ^~