/in/foo.cc: In function 'int main()':
/in/foo.cc:20:11: error: 'i' was not declared in this scope
    if (dp[i & 1][j]) std::cout << "yes\n";
           ^
/in/foo.cc:20:18: error: 'j' was not declared in this scope
    if (dp[i & 1][j]) std::cout << "yes\n";
                  ^