foo.cc: In function 'int findpos(int*, int, int, int)':
foo.cc:20:1: warning: control reaches end of non-void function [-Wreturn-type]
   20 | }
      | ^
foo.cc: In function 'int main()':
foo.cc:26:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   26 |   scanf("%d", &a[i]);
      |   ~~~~~^~~~~~~~~~~~~

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