foo.c: In function 'main':
foo.c:43:33: warning: left-hand operand of comma expression has no effect [-Wunused-value]
   43 |  for (i = n1, j = 0; i < n1 + n2, j < n2; i++, j++) {
      |                                 ^
foo.c:55:33: warning: left-hand operand of comma expression has no effect [-Wunused-value]
   55 |  for (i = n1, j = 0; i < n1 + n3, j < n3; i++, j++) {
      |                                 ^
foo.c:31:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   31 |  scanf("%d%d%d", &n1, &n2, &n3);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.c: In function 'shuru':
foo.c:71:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   71 |   scanf("%d", &a[i]);
      |   ^~~~~~~~~~~~~~~~~~

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