foo.cc: In function 'int main()':
foo.cc:13:19: warning: array subscript 3 is above array bounds of 'int [3]' [-Warray-bounds]
   13 |  c = a[1]+a[2]+a[3];
      |                ~~~^
foo.cc:6:6: note: while referencing 'a'
    6 |  int a[3],b[3],c,d,i;
      |      ^
foo.cc:14:9: warning: array subscript 3 is above array bounds of 'int [3]' [-Warray-bounds]
   14 |  d = b[3]+b[2]+b[1];
      |      ~~~^
foo.cc:6:11: note: while referencing 'b'
    6 |  int a[3],b[3],c,d,i;
      |           ^

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