foo.cc: In function 'int main()':
foo.cc:22:2: error: expected ',' or ';' before 'for'
   22 |  for(int i=0;i<n;i++)
      |  ^~~
foo.cc:22:14: error: 'i' was not declared in this scope
   22 |  for(int i=0;i<n;i++)
      |              ^
foo.cc:20:6: warning: unused variable 'm' [-Wunused-variable]
   20 |  int m[n];
      |      ^

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