foo.cc: In function 'int main()':
foo.cc:13:4: error: 'i' was not declared in this scope
   13 |    i++;
      |    ^
foo.cc: At global scope:
foo.cc:21:1: error: expected declaration before '}' token
   21 | }
      | ^
foo.cc:22:1: error: expected unqualified-id before 'for'
   22 | for( int i=o;i<n;i++){
      | ^~~
foo.cc:22:14: error: 'i' does not name a type
   22 | for( int i=o;i<n;i++){
      |              ^
foo.cc:22:18: error: 'i' does not name a type
   22 | for( int i=o;i<n;i++){
      |                  ^
foo.cc:28:2: error: expected unqualified-id before 'return'
   28 |  return 0;
      |  ^~~~~~
foo.cc:29:1: error: expected declaration before '}' token
   29 | }
      | ^

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