foo.cc: In function 'int main()':
foo.cc:27:9: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |  while(i<a.size()&&j<b.size())
      |        ~^~~~~~~~~
foo.cc:27:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |  while(i<a.size()&&j<b.size())
      |                    ~^~~~~~~~~
foo.cc:34:9: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |  while(i<a.size())
      |        ~^~~~~~~~~
foo.cc:36:9: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |  while(j<b.size())
      |        ~^~~~~~~~~
foo.cc:38:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |  for(int k=0;k<c.size();k++)
      |              ~^~~~~~~~~
foo.cc:27:8: warning: 'i' may be used uninitialized in this function [-Wmaybe-uninitialized]
   27 |  while(i<a.size()&&j<b.size())
      |        ^
foo.cc:36:8: warning: 'j' may be used uninitialized in this function [-Wmaybe-uninitialized]
   36 |  while(j<b.size())
      |        ^

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