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int a[35];
int n;
int dp[35][35];
int root[35][35];
void output(int left, int right) {
int r;
if (left>right) {
return;
}
r = root[left][right];
putint(r);
putch(32);
output(left, r-1); //递归左子树
output(r+1, right); //递归右子树
}
int solve(int l, int r) { //记忆化递归
int max1;
int max2;
int k;
int tmp;
if (dp[l][r]) {
return dp[l][r];
}
if (l == r) {
dp[l][r] = a[l];
root[l][r] = l;
}
max1 = solve(l+1,r) + solve(l,l); //l为根
if (max1 > dp[l][r]) {
dp[l][r] = max1;
root[l][r] = l;
}
max2 = solve(l,r-1) + solve(r,r); //r为根
if (max2 > dp[l][r]) {
dp[l][r] = max2;
root[l][r] = r;
}
k=l+1;
while (k<r) {
tmp = solve(l,k-1) * solve(k+1,r) + solve(k,k); //k为根
if (tmp > dp[l][r]) {
dp[l][r] = tmp;
root[l][r] = k; //记录根
}
k=k+1;
}
return dp[l][r];
}
int main() {
int i;
n = getint();
i=1;
while (i<=n) {
a[i] = getint();
dp[i][i] = a[i]; //分数
root[i][i] = i; //根节点
i=i+1;
}
putint(solve(1,n));
output(1,n); //输出前序遍历
return 0;
}
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