View Compilation Error

0_0_28526729_12993.cpp: In function 'int main()':
0_0_28526729_12993.cpp:21:18: error: expected primary-expression before ']' token
   double  bb[sum+]={0};
                  ^
0_0_28526729_12993.cpp:45:5: error: 'bb' was not declared in this scope
     bb[j]=min(bb[j],bb[j-a[i]]+b[i]);
     ^