foo.cc: In function 'double confuse(double)':
foo.cc:32:14: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   32 |     for(i=0;i<strlen(ch);i++){
      |             ~^~~~~~~~~~~
foo.cc:33:19: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   33 |         for (j=0;j<strlen(ch)-i-1;j++){
      |                  ~^~~~~~~~~~~~~~~
foo.cc:41:14: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   41 |     for(i=0;i<strlen(ch);i++){
      |             ~^~~~~~~~~~~

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