/in/foo.cc: In function 'int main()':
/in/foo.cc:35:13: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
   if(n==0&&m==0&t==0)
            ~^~~
/in/foo.cc:61:7: error: 'i' was not declared in this scope
   dfs(i,j,0);
       ^
/in/foo.cc:61:9: error: 'j' was not declared in this scope
   dfs(i,j,0);
         ^