foo.cc: In function 'void backtrack(std::vector<IndexedValue>&, std::vector<IndexedValue>&, int, std::vector<std::vector<IndexedValue> >&)':
foo.cc:19:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<IndexedValue>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |     for (int i = start; i < nums.size(); i++) {
      |                         ~~^~~~~~~~~~~~~
foo.cc: In function 'std::vector<std::vector<IndexedValue> > findIncreasingSubsequences(std::vector<int>&)':
foo.cc:34:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |     for (int i = 0; i < nums.size(); i++) {
      |                     ~~^~~~~~~~~~~~~

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