foo.cc:2:7: error: expected nested-name-specifier before 'spacemane'
    2 | using spacemane std;
      |       ^~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:6:13: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
    6 |         if(a=b=c)
      |            ~^~~~
foo.cc:7:17: error: expected primary-expression before 'else'
    7 |                 else
      |                 ^~~~
foo.cc:9:13: error: expected ')' before '!' token
    9 |         if(a!b!c)
      |           ~ ^
      |             )
foo.cc:10:17: error: expected primary-expression before 'else'
   10 |                 else
      |                 ^~~~

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