數字三角形 遞推和遞歸

#include<iostream>
#include<algorithm>
using namespace std;
#define MAX 101
int D[MAX][MAX];
int * MaxSum;
int n;
void Solve_1()  //遞推
{
    MaxSum = D[n];
    for(int i = n-1; i>=1; --i)
        for(int j = 1; j<=i; ++j)
            MaxSum[j] = max(MaxSum[j],MaxSum[j+1]) + D[i][j];
    cout << MaxSum[1] << endl;
}
int maxsum[MAX][MAX];
int Maxsum(int i,int j) 
{
    if(maxsum[i][j] != -1)
        return maxsum[i][j];
    if(i == n)
        maxsum[i][j] = D[i][j];
    else{
        int x = Maxsum(i+1,j);
        int y = Maxsum(i+1,j+1);
        maxsum[i][j] = max(x,y) + D[i][j];
    }
    return maxsum[i][j];
}
void Solve_2() //遞推
{
    for(int i = 1; i <= n; ++i)
        for(int j = 1; j <= i; ++j)
            maxsum[i][j] = -1;
    cout << Maxsum(1,1);
}
int main()
{
    cin >> n;
    for(int i = 1; i <= n; ++i)
        for(int j = 1; j <= i; ++j)
            cin >> D[i][j];
    Solve_2();
    return 0;
}