/in/foo.cc: In function 'void combine(int*, int*, int*, int, int, int)':
/in/foo.cc:25:4: error: 'a' was not declared in this scope
    a[new_point--] = a1[a1_point--];
    ^
/in/foo.cc:29:4: error: 'a' was not declared in this scope
    a[new_point--] = a2[a2_point--];
    ^
/in/foo.cc:34:4: error: 'a' was not declared in this scope
    a[new_point--] = a2[a2_point--];
    ^
/in/foo.cc:38:4: error: 'a' was not declared in this scope
    a[new_point--] = a3[a3_point--];
    ^
/in/foo.cc: At global scope:
/in/foo.cc:42:2: error: expected unqualified-id before 'while'
  while(a1_point >= 0)
  ^~~~~
/in/foo.cc:47:2: error: expected unqualified-id before 'while'
  while(a2_point >= 0)
  ^~~~~
/in/foo.cc:51:2: error: expected unqualified-id before 'while'
  while(a3_point >= 0)
  ^~~~~
/in/foo.cc:56:2: error: expected unqualified-id before 'return'
  return ;
  ^~~~~~
/in/foo.cc:57:1: error: expected declaration before '}' token
 }
 ^