The Triangle 数字三角形（C++）

Description
7
3 8
8 1 0
2 7 4 4
4 5 2 6 5
（Figure 1)

Figure 1 shows a number triangle. Write a program that calculates the highest sum of numbers passed
on a route that starts at the top and ends somewhere on the base. Each step can go either diagonally
down to the left or diagonally down to the right.
给出一个数字三角形，你从[1,1]开始出发，走到最后一行。每次站在一个点上时，可以向下走，或者向右下走。
将经过的数字加起来，希望其和最大。
Input
The first line contains one integer N: the number of rows in the triangle.
The following N lines describe the data of the triangle.
The number of rows in the triangle is > 1 but <= 100.
The numbers in the triangle, all integers, are between 0 and 99.
Output
Your program is to write to standard output. The highest sum is written as an integer.
Sample Input

5
7
3 8
8 1 0
2 7 4 4
4 5 2 6 5

Sample Output

30

HINT

这题我们可以用记忆化搜索+枚举法，将每一条路记下来，并枚举得出最大值
下面是代码：

#include<bits/stdc++.h>
using namespace std;
int a[101][101],d[