/in/foo.cc: In function 'int main(int, const char**)':
/in/foo.cc:27:7: warning: 'fn' may be used uninitialized in this function [-Wmaybe-uninitialized]
     fn+=(n-p*q/2)*f[q]%10000;
     ~~^~~~~~~~~~~~~~~~~~~~~~
/in/foo.cc:5:11: warning: 'p' may be used uninitialized in this function [-Wmaybe-uninitialized]
     int n,p,q,i;
           ^