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Can anyone teach me why I got TLE in this problem?
I tried to modify data structure several time, but result was still the same.
Also, according to previous posts, the technique used in this problem is DP, and I used DP with memorization, so I really can't figure where I did wrong. :o
Thanks ...

#include <stdio.h>
#include <list>
#include <string>
#include<vector>
using namespace std;

const int MAXROW=1024;
const int MAXCOL=18000;

enum otype{oadd,ominus,otime,odivide,lpar,rpar};
class bignum
{
protected:
vector<int> val;
void delzero();
void setval(vector<int>& target);
public ...