foo.cc: In function 'int main()':
foo.cc:35:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |   for(int i=0;i<v.size()-1;i++) {
      |               ~^~~~~~~~~~~
foo.cc:43:26: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   43 |     for(int j=0;v2.size()<len;j++) {
      |                 ~~~~~~~~~^~~~
foo.cc:49:35: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   49 |     for(int j=v.size()-1;v1.size()<len;j--) {
      |                          ~~~~~~~~~^~~~
foo.cc:60:26: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   60 |     for(int j=0;v2.size()<len;j++) {
      |                 ~~~~~~~~~^~~~
foo.cc:65:35: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   65 |     for(int j=v.size()-1;v1.size()<len+1;j--) {
      |                          ~~~~~~~~~^~~~~~

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