foo.cc: In function 'int main()':
foo.cc:9:21: warning: format '%s' expects argument of type 'char*', but argument 2 has type 'char (*)[3000]' [-Wformat=]
       scanf("%s",&ch);
                  ~~~^
foo.cc:9:12: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
       scanf("%s",&ch);
       ~~~~~^~~~~~~~~~

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