foo.cc: In function 'int main()':
foo.cc:11:17: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   11 |  for (i = 0 ; i < strlen(s); i++)
      |               ~~^~~~~~~~~~~
foo.cc:8:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf("%s",s);
      |  ~~~~~^~~~~~~~

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