foo.cc: In function 'll get_value(char*)':
foo.cc:20:20: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   20 |  for (int i = 0; i < strlen(s); i++)
      |                  ~~^~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:41:11: warning: format '%s' expects argument of type 'char*', but argument 2 has type 'char (*)[20]' [-Wformat=]
   41 |   scanf("%s", &a[i].s);
      |          ~^   ~~~~~~~
      |           |   |
      |           |   char (*)[20]
      |           char*
foo.cc:29:12: warning: unused variable 'k' [-Wunused-variable]
   29 |  int i, j, k;
      |            ^
foo.cc:37:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   37 |  scanf("%d %s", &n, str);
      |  ~~~~~^~~~~~~~~~~~~~~~~~
foo.cc:41:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   41 |   scanf("%s", &a[i].s);
      |   ~~~~~^~~~~~~~~~~~~~~

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