foo.c: In function 'main':
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%d%d",&n,&m);
      |  ^~~~~~~~~~~~~~~~~~~
foo.c:9:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    9 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:13:8: warning: 'cnt' may be used uninitialized in this function [-Wmaybe-uninitialized]
   13 |     cnt++;
      |     ~~~^~

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