foo.cc: In function 'int main()':
foo.cc:3:1: error: 'cin' was not declared in this scope
 cin>>n;
 ^~~
foo.cc:3:1: note: suggested alternative: 'main'
 cin>>n;
 ^~~
 main
foo.cc:21:1: error: 'cout' was not declared in this scope
 cout<<n<<"="<<i<<"+"<<j;
 ^~~~

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