foo.cc: In function 'int main()':
foo.cc:12:21: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   12 |     for(int i = 0;i < strlen(s1);i++)
      |                   ~~^~~~~~~~~~~~
foo.cc:14:26: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   14 |         for(int j = 0; j < strlen(s2); j++)
      |                        ~~^~~~~~~~~~~~
foo.cc:21:20: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   21 |     for(int i = 0;i< strlen(s1);i++)
      |                   ~^~~~~~~~~~~~

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