foo.cc: In function 'int main()':
foo.cc:14:15: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   14 |     for (i=0;i<strlen(s);i++)
      |              ~^~~~~~~~~~
foo.cc:46:40: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
   46 |     if (ans<=0.000&&ans>-0.0005) printf("%c=0.000",c);
      |                                  ~~~~~~^~~~~~~~~~~~~~

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