foo.cc: In function 'int main()':
foo.cc:4:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    4 |  scanf("%d%d%d%d%d%d%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f,&g,&h,&i,&j,&k,&l);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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