foo.c: In function 'SetInter':
foo.c:46:6: warning: unused variable 'j' [-Wunused-variable]
   46 |  int j;
      |      ^
foo.c: In function 'main':
foo.c:66:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   66 |  scanf("%d %d %d", &n1, &n2, &n3);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:72:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   72 |   scanf("%d", &a1[i]);
      |   ^~~~~~~~~~~~~~~~~~~
foo.c:75:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   75 |   scanf("%d", &a2[i]);
      |   ^~~~~~~~~~~~~~~~~~~
foo.c:78:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   78 |   scanf("%d", &a3[i]);
      |   ^~~~~~~~~~~~~~~~~~~

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