foo.cc: In function 'int main()':
foo.cc:11:10: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   11 | while (f = 0)
      |        ~~^~~
foo.cc:14:19: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
   14 |         if (e % a == 0 & e % b == 0)
      |             ~~~~~~^~~~
foo.cc:7:15: warning: variable 'c' set but not used [-Wunused-but-set-variable]
    7 | long  int a,b,c,e,f;
      |               ^

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