foo.cc: In function 'int main()':
foo.cc:4:2: error: 'cin' was not declared in this scope
    4 |  cin>>x;
      |  ^~~
foo.cc:19:4: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
   19 |    else
      |    ^~~~
foo.cc:29:5: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'else'
   29 |     if(flag!=0)
      |     ^~
foo.cc:30:6: error: 'cout' was not declared in this scope
   30 |      cout<<i<<'+'<<x-i<<'='<<x<<endl;
      |      ^~~~
foo.cc:30:33: error: 'endl' was not declared in this scope
   30 |      cout<<i<<'+'<<x-i<<'='<<x<<endl;
      |                                 ^~~~

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