foo.c: In function 'prime':
foo.c:7:3: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
    7 |   for(int i=2;i<=a;i++)
      |   ^~~
foo.c:10:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   10 |    if(a==1)
      |    ^~
foo.c: In function 'main':
foo.c:19:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   19 |  scanf("%d",&a);
      |  ^~~~~~~~~~~~~~

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