foo.c: In function 'hah':
foo.c:7:16: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
    7 |         while (c = a % b)
      |                ^
foo.c:5:13: warning: unused variable 'd' [-Wunused-variable]
    5 |         int d = a * b;
      |             ^
foo.c: In function 'main':
foo.c:16:15: warning: unused variable 'x' [-Wunused-variable]
   16 |         int n,x=0,m=0;
      |               ^

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