foo.cc: In function 'int main()':
foo.cc:31:12: warning: unused variable 'ans' [-Wunused-variable]
   31 |  int a, b, ans=0;
      |            ^~~
foo.cc:32:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   32 |  scanf ("%d%d",&a ,&b);
      |  ~~~~~~^~~~~~~~~~~~~~~

Found 10 testcases.
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