#include <iostream>
using namespace std;
int N, A[5001];
int cst[5001][5001], DP[5001][5001];
int main()
{
cin >> N;
for (int i = 0; i < N; i++) cin >> A[i];
for (int i = 0; i < N; i++)
{
int sumL = 0, sumR = 0, l = i - 1, r = i;
while (l >= 0 && r < N)
{
if (sumL + A[l] < sumR + A[r]) {sumL += A[l--];}
else {sumR += A[r++];}
if (l >= 0 && r < N && sumL == sumR) {cst[i][l] = 1; cst[i][r] = 1;}
}
for (int j = i + 1; j < N; j++) cst[i][j] = cst[i][j - 1] + cst[i][j];
for (int j = i - 2; j >= 0; j--) cst[i][j] = cst[i][j + 1] + cst[i][j];
}
for (int i = 0; i < N; i++)
{
for (int j = 0; j <= i; j++)
{
//cerr << i << " " << j << " DP\n";
for (int k = j - 1; k >= 0; k--)
{
DP[i][j] = max(DP[i][j], DP[j - 1][k] + min(cst[j][i], cst[j][k]));
//cerr << j - 1 << " " << k << " " << DP[j - 1][k] << " " << min(cst[j][i], cst[j][k]) << "\n";
}
//cerr << "DPF: " << i << " " << j << " " << DP[i][j] << "\n";
}
}
int res = 0;
for (int i = 0; i < N; i++) {res = max(res, DP[N - 1][i]);}
cout << res << "\n";
return 0;
}
