foo.cc: In function 'int main()':
foo.cc:18:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d%d%d%d",&n,&m,&q,&u,&v,&t);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:20:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(int i=1;i<=n;i++) scanf("%d",&a[i]);
                           ~~~~~^~~~~~~~~~~~

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