foo.c: In function 'main':
foo.c:4:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&n);
 ^~~~~~~~~~~~~~
foo.c:5:35: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 for(int i=1;i<=n;i++){long long x;scanf("%lld",&x);ans+=x;}
                                   ^~~~~~~~~~~~~~~~

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