foo.cc: In function 'bool find(int, std::vector<int>&)':
foo.cc:40:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   40 |  for (int i = 0;i < v.size();i++)
      |                 ~~^~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:53:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   53 |  for (int i = 0;i < s1.size();)
      |                 ~~^~~~~~~~~~~

[Hydro](https://hydro.ac)提供评测服务