foo.cc: In function 'void SortedSeqList(std::vector<int>&, std::vector<int>&, std::vector<int>&)':
foo.cc:7:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int k=0;k<a.size()+b.size();k++)
              ~^~~~~~~~~~~~~~~~~~
foo.cc:9:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(a[i]>b[j]&&j<b.size()||i>=a.size())
                 ~^~~~~~~~~
foo.cc:9:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(a[i]>b[j]&&j<b.size()||i>=a.size())
                             ~^~~~~~~~~~
foo.cc:9:15: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if(a[i]>b[j]&&j<b.size()||i>=a.size())
foo.cc:15:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if(a[i]<b[j]&&i<a.size()||j>=b.size())
                  ~^~~~~~~~~
foo.cc:15:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if(a[i]<b[j]&&i<a.size()||j>=b.size())
                              ~^~~~~~~~~~
foo.cc:15:16: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    if(a[i]<b[j]&&i<a.size()||j>=b.size())
foo.cc: In function 'void output(std::vector<int>&)':
foo.cc:24:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<a.size();i++)
              ~^~~~~~~~~

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