foo.cc: In function 'int main()':
foo.cc:28:16: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |         while(i<a.size()&&j<b.size()){
      |               ~^~~~~~~~~
foo.cc:28:28: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |         while(i<a.size()&&j<b.size()){
      |                           ~^~~~~~~~~
foo.cc:37:16: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   37 |         while(i<a.size()){
      |               ~^~~~~~~~~
foo.cc:41:16: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |         while(j<b.size()){
      |               ~^~~~~~~~~
foo.cc:45:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |         for(int i=0;i<c.size();i++){
      |                     ~^~~~~~~~~

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