foo.c: In function 'main':
foo.c:26:7: error: 'm' undeclared (first use in this function)
   26 |  gys1=m;
      |       ^
foo.c:26:7: note: each undeclared identifier is reported only once for each function it appears in
foo.c:25:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   25 |  scanf("%d",&t);
      |  ^~~~~~~~~~~~~~
foo.c:29:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   29 |     scanf("%d",&n);
      |     ^~~~~~~~~~~~~~

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