foo.cc: In function 'int main()':
foo.cc:9:12: warning: array subscript 3 is above array bounds of 'long long int [3]' [-Warray-bounds]
    9 |         a[3]=n%10;
      |         ~~~^
foo.cc:3:13: note: while referencing 'a'
    3 | long long n,a[3];
      |             ^
foo.cc:11:18: warning: array subscript 3 is above array bounds of 'long long int [3]' [-Warray-bounds]
   11 |         cout<<a[3]<<a[2]<<a[1];
      |                  ^
foo.cc:3:13: note: while referencing 'a'
    3 | long long n,a[3];
      |             ^

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