Exploring Pyramids poj2795

训练指南上给图后三幅有错误

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <queue>
#include <algorithm>
#include <vector>
#include <cstring>
#include <stack>
#include <cctype>
#include <utility>   
#include <map>
#include <string>  
#include <climits> 
#include <set>
#include <string> 
#include <sstream>
#include <utility>   
#include <ctime>
 
using std::priority_queue;
using std::vector;
using std::swap;
using std::stack;
using std::sort;
using std::max;
using std::min;
using std::pair;
using std::map;
using std::string;
using std::cin;
using std::cout;
using std::set;
using std::queue;
using std::string;
using std::istringstream;
using std::make_pair;
using std::greater;
using std::endl;

typedef long long LL;
const int MAXN(310);
const LL MOD(1000000000);

char str[MAXN];
LL table[MAXN][MAXN];

int main()
{
	while(~scanf("%s", str+1))
	{
		int len = strlen(str+1);
		memset(table, 0, sizeof(table));
		for(int i = 1; i <= len; ++i)
			table[i][i] = 1LL;
		for(int l = 2; l <= len; ++l)
		{
			int lim = len-l+1;
			for(int i = 1; i <= lim; ++i)
			{
				int j = i+l-1;
				if(str[i] != str[j])
				{
					table[i][j] = 0LL;
					continue;
				}
				for(int k = i+1; k <= j; ++k)
					if(str[i] == str[k])
						table[i][j] = (table[i][j]+table[i+1][k-1]*table[k][j])%MOD;
			}
		}
		printf("%I64d\n", table[1][len]);
	}
	return 0;
}