foo.c: In function 'main':
foo.c:4:2: warning: parameter names (without types) in function declaration
    4 |  int a[100000],n,i,j,fm,gcd(m,n);
      |  ^~~
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    5 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:8:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |   scanf("%d%d",&a[2*i],&a[2*i+1]);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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