foo.cc: In function 'void addNum(std::vector<Num>&, Num&)':
foo.cc:123:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Num>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  123 |  for(int i=0;i<v.size();i++) {
      |              ~^~~~~~~~~
foo.cc: In function 'Num& getGoodOne(int, int)':
foo.cc:160:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Num>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  160 |  for(int i=0;i<vi.size();i++) {
      |              ~^~~~~~~~~~
foo.cc: In function 'void preCalc()':
foo.cc:215:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Num>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  215 |    for(int k=0;k<preBuild.size();k++) {
      |                ~^~~~~~~~~~~~~~~~
foo.cc:216:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Num>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  216 |     for(int k2=k+1;k2<preBuild.size();k2++) {
      |                    ~~^~~~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:233:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  233 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
foo.cc:243:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  243 |  for(int i=0;i<3;i++) scanf("%d%d", &p[i], &q[i]);
      |                       ~~~~~^~~~~~~~~~~~~~~~~~~~~~

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