Accepted
/in/foo.cc: In function 'void bfs()':
/in/foo.cc:88:6: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
if(used[u][v] && a[s][t]!=0)
^
/in/foo.cc: In function 'void bfs()':
/in/foo.cc:88:6: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
if(used[u][v] && a[s][t]!=0)
^
