foo.cc: In function 'int main()':
foo.cc:9:22: warning: comparison of integer expressions of different signedness: 'int' and 'const long unsigned int' [-Wsign-compare]
    9 |         for(int i=0;i<max(strlen(a),strlen(b));i++)
      |                     ~^~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:20:15: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   20 |         for(;i<strlen(a);i++)
      |              ~^~~~~~~~~~
foo.cc:23:15: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   23 |         for(;i<strlen(a);i++)
      |              ~^~~~~~~~~~

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