/in/foo.cc: In function 'void SPFA()':
/in/foo.cc:40:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i=0;i<Adj[u].size();i++)
                     ~^~~~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:83:12: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
    if((fi&1==1)&&(a[j]-fi==a[i])&&find(fi))
           ~^~~