foo.c: In function 'main':
foo.c:4:11: warning: unused variable 'cnt' [-Wunused-variable]
     int n,cnt=0;
           ^~~
foo.c:5:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
     ^~~~~~~~~~~~~~
foo.c:10:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d",&s[i]);
         ^~~~~~~~~~~~~~~~~

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