foo.cc: In function 'int main()':
foo.cc:10:20: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   10 |  while(str1.size() < size){
      |        ~~~~~~~~~~~~^~~~~~
foo.cc:28:10: error: expected '}' at end of input
   28 |  return 0;
      |          ^
foo.cc:3:11: note: to match this '{'
    3 | int main(){
      |           ^

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