foo.cc: In function 'int main()':
foo.cc:43:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |  for (int i = 0; i < segs.size(); i++) {
      |                  ~~^~~~~~~~~~~~~
foo.cc:33:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   33 |  scanf("%d%d", &L, &n);
      |  ~~~~~^~~~~~~~~~~~~~~~
foo.cc:38:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   38 |   scanf("%d%d", &l, &r);
      |   ~~~~~^~~~~~~~~~~~~~~~

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