View Compilation Error

0_0_21152992_19452.cpp: In function 'int main()':
0_0_21152992_19452.cpp:34:38: error: 'w' was not declared in this scope
                 for(int j=20000;j>=k*w[i];j--)
                                      ^
0_0_21152992_19452.cpp:36:21: error: 'Dp' was not declared in this scope
                     Dp[j]=min(Dp[j],Dp[j-k*w[i]]+k);
                     ^