/in/foo.cc: In function 'bigint operator+(const bigint&, const bigint&)':
/in/foo.cc:17:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<a.size()||i<b.size();++i){
              ~^~~~~~~~~
/in/foo.cc:17:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<a.size()||i<b.size();++i){
                          ~^~~~~~~~~
/in/foo.cc:18:7: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(i<a.size()) p+=a[i]; if(i<b.size()) p+=b[i];
      ~^~~~~~~~~
/in/foo.cc:18:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   if(i<a.size()) p+=a[i]; if(i<b.size()) p+=b[i];
   ^~
/in/foo.cc:18:27: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
   if(i<a.size()) p+=a[i]; if(i<b.size()) p+=b[i];
                           ^~
/in/foo.cc:18:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(i<a.size()) p+=a[i]; if(i<b.size()) p+=b[i];
                              ~^~~~~~~~~
/in/foo.cc:21:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if(p) ans.push_back(p); return ans;
  ^~
/in/foo.cc:21:26: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
  if(p) ans.push_back(p); return ans;
                          ^~~~~~
/in/foo.cc: In function 'bigint operator*(const bigint&, int)':
/in/foo.cc:25:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<a.size();++i){
              ~^~~~~~~~~
/in/foo.cc:28:2: warning: this 'while' clause does not guard... [-Wmisleading-indentation]
  while(p) ans.push_back(p%mod),p/=mod; return ans;
  ^~~~~
/in/foo.cc:28:40: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'while'
  while(p) ans.push_back(p%mod),p/=mod; return ans;
                                        ^~~~~~
/in/foo.cc: In function 'void check(int, int)':
/in/foo.cc:64:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   if(len==1&&d[1]==1) return; --d[1];
   ^~
/in/foo.cc:64:31: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
   if(len==1&&d[1]==1) return; --d[1];
                               ^~