foo.cc: In function 'int main()':
foo.cc:24:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     int T;scanf("%d",&T);
           ~~~~~^~~~~~~~~
foo.cc:27:22: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         int k,n;scanf("%d%d",&k,&n);
                 ~~~~~^~~~~~~~~~~~~~

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