foo.c: In function 'main':
foo.c:7:7: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
    7 | while(r=m%n)
      |       ^
foo.c:4:11: warning: unused variable 'x' [-Wunused-variable]
    4 | int m,n,r,x,d;
      |           ^
foo.c:12:9: warning: 'd' may be used uninitialized in this function [-Wmaybe-uninitialized]
   12 |         printf("%d %d",n,d);
      |         ^~~~~~~~~~~~~~~~~~~

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