foo.cc: In function 'int main()':
foo.cc:11:18: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   11 |     for(int i=0;i<strlen(s1);i++)
      |                 ~^~~~~~~~~~~
foo.cc:12:22: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   12 |         for(int j=0;j<strlen(s2);j++)
      |                     ~^~~~~~~~~~~

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