foo.cc: In function 'int main()':
foo.cc:9:2: error: 'strlwr' was not declared in this scope; did you mean 'strstr'?
    9 |  strlwr(a);
      |  ^~~~~~
      |  strstr
foo.cc:7:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%s", a);
      |  ~~~~~^~~~~~~~~
foo.cc:8:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf("%s", b);
      |  ~~~~~^~~~~~~~~

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