foo.cc: In function 'int main()':
foo.cc:40:25: error: expected ')' before 'for'
   40 |     for(int k=0;k<=9;k++
      |        ~                ^
      |                         )
   41 | 
   42 |         for(int i=0;i<=9;i++)
      |         ~~~              
foo.cc:46:5: error: expected primary-expression before 'for'
   46 |     for(int i=0;i<a.length();i++)
      |     ^~~
foo.cc:46:17: error: 'i' was not declared in this scope
   46 |     for(int i=0;i<a.length();i++)
      |                 ^

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