foo.cc: In function 'int main()':
foo.cc:6:9: error: 'i' was not declared in this scope
     for(i=1001,i<=9999,i++)
         ^
foo.cc:9:5: error: expected primary-expression before 'return'
     return 0;
     ^~~~~~
foo.cc:9:5: error: expected ';' before 'return'
foo.cc:9:5: error: expected primary-expression before 'return'
foo.cc:9:5: error: expected ')' before 'return'

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