/in/foo.cc: In function 'void read(t_&)':
/in/foo.cc:11:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if(t=='-')flag=1,t=getchar();x=t-'0';
  ^~
/in/foo.cc:11:31: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
  if(t=='-')flag=1,t=getchar();x=t-'0';
                               ^
/in/foo.cc: In function 'int lca(int, int)':
/in/foo.cc:60:13: warning: self-comparison always evaluates to true [-Wtautological-compare]
   if(f[i][r]==f[i][r])continue;
      ~~~~~~~^~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:111:8: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   mid=l+r>>1;
       ~^~