foo.cc: In function 'void digui(std::vector<int>, std::vector<std::vector<int> >, int, int&)':
foo.cc:12:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |  for(int i = 1;i<test.size();i++)
      |                ~^~~~~~~~~~~~
foo.cc:19:14: warning: comparison of integer expressions of different signedness: 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   19 |  if(cd.size()<t)
      |     ~~~~~~~~~^~
foo.cc:23:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |  for(int i = 0;i<cd.size();i++)
      |                ~^~~~~~~~~~
foo.cc:25:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |   for(int j = 0;j<cd[0].size();j++)
      |                 ~^~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:39:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   39 |  freopen("test.txt","r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

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