/in/foo.cc: In member function 'void Graph::judge(int, int, int)':
/in/foo.cc:37:22: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
    if((sta & (1 << i - 1)) && f[x][i] && i != fa)
                    ~~^~~
/in/foo.cc: In member function 'bool Graph::check(int)':
/in/foo.cc:43:21: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
    if(sta & (1 << i - 1))
                   ~~^~~
/in/foo.cc:46:22: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
    if((sta & (1 << i - 1)) && (!vis[i])) return 0;
                    ~~^~~