/in/foo.cc: In function 'int check1(int, int, int, int)':
/in/foo.cc:27:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   if(l==x)l++;if(r==x)r--;
   ^~
/in/foo.cc:27:15: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
   if(l==x)l++;if(r==x)r--;
               ^~
/in/foo.cc: In function 'int dfs(int, int, int)':
/in/foo.cc:58:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
    int mid=l+r>>1;
            ~^~
/in/foo.cc:70:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
    int mid=l+r>>1;
            ~^~
/in/foo.cc: In function 'int main()':
/in/foo.cc:100:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int mid=l+r>>1;
           ~^~