View Compilation Error

0_0_36118801_14247.cpp: In function 'int main()':
0_0_36118801_14247.cpp:20:42: error: 'cost' was not declared in this scope
       dp[i][j] = max( dp[i][j] , dp[i][j-cost[k]]+val[k] );
                                          ^
0_0_36118801_14247.cpp:20:47: error: 'k' was not declared in this scope
       dp[i][j] = max( dp[i][j] , dp[i][j-cost[k]]+val[k] );
                                               ^
0_0_36118801_14247.cpp:20:51: error: 'val' was not declared in this scope
       dp[i][j] = max( dp[i][j] , dp[i][j-cost[k]]+val[k] );
                                                   ^