foo.cc: In function 'int main()':
foo.cc:6:20: error: expected initializer before numeric constant
    6 |         int a[100] 0 };
      |                    ^
foo.cc: At global scope:
foo.cc:10:9: error: 'cin' does not name a type
   10 |         cin >> x;
      |         ^~~
foo.cc:11:9: error: expected unqualified-id before 'while'
   11 |         while (x != 0)
      |         ^~~~~
foo.cc:16:9: error: 'i' does not name a type
   16 |         i--; int y = 1;
      |         ^
foo.cc:17:9: error: expected unqualified-id before 'for'
   17 |         for (; i >= 0; i--)
      |         ^~~
foo.cc:17:16: error: 'i' does not name a type
   17 |         for (; i >= 0; i--)
      |                ^
foo.cc:17:24: error: 'i' does not name a type
   17 |         for (; i >= 0; i--)
      |                        ^
foo.cc:22:9: error: 'cout' does not name a type
   22 |         cout << ret;
      |         ^~~~
foo.cc:23:9: error: expected unqualified-id before 'return'
   23 |         return 0;
      |         ^~~~~~
foo.cc:24:1: error: expected declaration before '}' token
   24 | }
      | ^

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