foo.cc: In function 'int main()':
foo.cc:148:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d", &N);
 ~~~~~^~~~~~~~~~
foo.cc:149:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 rep (i, N) scanf("%d", &A[i]);
            ~~~~~^~~~~~~~~~~~~

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