foo.c: In function 'main':
foo.c:6:10: warning: unused variable 'j' [-Wunused-variable]
    6 |  int n,i,j,ans=0,left,right;
      |          ^
foo.c:8:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:9:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    9 |  scanf("%s",s);
      |  ^~~~~~~~~~~~~
foo.c:16:7: warning: 'left' may be used uninitialized in this function [-Wmaybe-uninitialized]
   16 |  for(i=left+1;i<n;i++)
      |      ~^~~~~~~

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