/in/foo.cc: In function 'int main()':
/in/foo.cc:13:20: warning: left operand of comma operator has no effect [-Wunused-value]
    if(j>=a[i]) b[i,j]=max(b[i-1,j-a[i]]+a[i],b[i-1,j]);
                    ^
/in/foo.cc:13:30: warning: left operand of comma operator has no effect [-Wunused-value]
    if(j>=a[i]) b[i,j]=max(b[i-1,j-a[i]]+a[i],b[i-1,j]);
                             ~^~
/in/foo.cc:13:49: warning: left operand of comma operator has no effect [-Wunused-value]
    if(j>=a[i]) b[i,j]=max(b[i-1,j-a[i]]+a[i],b[i-1,j]);
                                                ~^~
/in/foo.cc:13:54: error: no matching function for call to 'max(int*, int [20001])'
    if(j>=a[i]) b[i,j]=max(b[i-1,j-a[i]]+a[i],b[i-1,j]);
                                                      ^
In file included from /usr/include/c++/6/bits/char_traits.h:39:0,
                 from /usr/include/c++/6/ios:40,
                 from /usr/include/c++/6/istream:38,
                 from /usr/include/c++/6/sstream:38,
                 from /usr/include/c++/6/complex:45,
                 from /usr/include/c++/6/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:52,
                 from /in/foo.cc:1:
/usr/include/c++/6/bits/stl_algobase.h:219:5: note: candidate: template<class _Tp> const _Tp& std::max(const _Tp&, const _Tp&)
     max(const _Tp& __a, const _Tp& __b)
     ^~~
/usr/include/c++/6/bits/stl_algobase.h:219:5: note:   template argument deduction/substitution failed:
/in/foo.cc:13:54: note:   deduced conflicting types for parameter 'const _Tp' ('int*' and 'int [20001]')
    if(j>=a[i]) b[i,j]=max(b[i-1,j-a[i]]+a[i],b[i-1,j]);
                                                      ^
In file included from /usr/include/c++/6/bits/char_traits.h:39:0,
                 from /usr/include/c++/6/ios:40,
                 from /usr/include/c++/6/istream:38,
                 from /usr/include/c++/6/sstream:38,
                 from /usr/include/c++/6/complex:45,
                 from /usr/include/c++/6/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:52,
                 from /in/foo.cc:1:
/usr/include/c++/6/bits/stl_algobase.h:265:5: note: candidate: template<class _Tp, class _Compare> const _Tp& std::max(const _Tp&, const _Tp&, _Compare)
     max(const _Tp& __a, const _Tp& __b, _Compare __comp)
     ^~~
/usr/include/c++/6/bits/stl_algobase.h:265:5: note:   template argument deduction/substitution failed:
/in/foo.cc:13:54: note:   deduced conflicting types for parameter 'const _Tp' ('int*' and 'int [20001]')
    if(j>=a[i]) b[i,j]=max(b[i-1,j-a[i]]+a[i],b[i-1,j]);
                                                      ^
In file included from /usr/include/c++/6/algorithm:62:0,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:65,
                 from /in/foo.cc:1:
/usr/include/c++/6/bits/stl_algo.h:3459:5: note: candidate: template<class _Tp> _Tp std::max(std::initializer_list<_Tp>)
     max(initializer_list<_Tp> __l)
     ^~~
/usr/include/c++/6/bits/stl_algo.h:3459:5: note:   template argument deduction/substitution failed:
/in/foo.cc:13:54: note:   mismatched types 'std::initializer_list<_Tp>' and 'int*'
    if(j>=a[i]) b[i,j]=max(b[i-1,j-a[i]]+a[i],b[i-1,j]);
                                                      ^
In file included from /usr/include/c++/6/algorithm:62:0,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:65,
                 from /in/foo.cc:1:
/usr/include/c++/6/bits/stl_algo.h:3465:5: note: candidate: template<class _Tp, class _Compare> _Tp std::max(std::initializer_list<_Tp>, _Compare)
     max(initializer_list<_Tp> __l, _Compare __comp)
     ^~~
/usr/include/c++/6/bits/stl_algo.h:3465:5: note:   template argument deduction/substitution failed:
/in/foo.cc:13:54: note:   mismatched types 'std::initializer_list<_Tp>' and 'int*'
    if(j>=a[i]) b[i,j]=max(b[i-1,j-a[i]]+a[i],b[i-1,j]);
                                                      ^
/in/foo.cc:14:13: warning: left operand of comma operator has no effect [-Wunused-value]
    else b[i,j]=b[i-1,j];
             ^
/in/foo.cc:14:19: warning: left operand of comma operator has no effect [-Wunused-value]
    else b[i,j]=b[i-1,j];
                  ~^~
/in/foo.cc:14:23: error: invalid array assignment
    else b[i,j]=b[i-1,j];
                       ^
/in/foo.cc:10:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(int i=1;i<=n;i++)
  ^~~
/in/foo.cc:16:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
   cout<<v-b[n][v];
   ^~~~