foo.cc: In function 'int main()':
foo.cc:7:22: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
    7 |         for(int i=0;i<strlen(c);i++)
      |                     ~^~~~~~~~~~
foo.cc:30:22: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   30 |         for(int i=0;i<strlen(c)-1;i++)
      |                     ~^~~~~~~~~~~~
foo.cc:42:22: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   42 |         for(int i=0;i<strlen(c);i++)
      |                     ~^~~~~~~~~~

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