foo.cc: In function 'int main()':
foo.cc:17:10: warning: format '%s' expects argument of type 'char*', but argument 2 has type 'char (*)[110]' [-Wformat=]
   17 |  scanf("%s",&a);
      |         ~^  ~~
      |          |  |
      |          |  char (*)[110]
      |          char*
foo.cc:18:10: warning: format '%s' expects argument of type 'char*', but argument 2 has type 'char (*)[110]' [-Wformat=]
   18 |  scanf("%s",&b);
      |         ~^  ~~
      |          |  |
      |          |  char (*)[110]
      |          char*
foo.cc:19:15: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   19 |  for(int i=0;i<strlen(a);i++) a[i]=toupper(a[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(int i=0;i<strlen(b);i++) b[i]=toupper(b[i]);
      |              ~^~~~~~~~~~
foo.cc:17:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   17 |  scanf("%s",&a);
      |  ~~~~~^~~~~~~~~
foo.cc:18:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   18 |  scanf("%s",&b);
      |  ~~~~~^~~~~~~~~

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