代码

#include <cstdio>#include <iostream>#define N 41#define max(x, y) ((x) > (y) ? (x) : (y))int n;int a[N], f[N][N], pre[N][N];inline int read(){	int x = 0, f = 1;	char ch = getchar();	for(; !isdigit(ch); ch = getchar()) if(ch == ‘-‘) f = -1;	for(; isdigit(ch); ch = getchar()) x = (x << 1) + (x << 3) + ch - ‘0‘;	return x * f;}inline void solve(int l, int r){	printf("%d ", pre[l][r]);	if(l <= pre[l][r] - 1) solve(l, pre[l][r] - 1);	if(pre[l][r] + 1 <= r) solve(pre[l][r] + 1, r);}int main(){	int i, j, k;	n = read();	for(i = 1; i <= n; i++) f[i][i] = read(), pre[i][i] = i;	for(i = n; i >= 1; i--)		for(j = i + 1; j <= n; j++)		{			if(f[i][i] + f[i + 1][j] > f[i][j])				f[i][j] = f[i][i] + f[i + 1][j], pre[i][j] = i;			for(k = i + 1; k < j; k++)				if(f[i][k - 1] * f[k + 1][j] + f[k][k] > f[i][j])					f[i][j] = f[i][k - 1] * f[k + 1][j] + f[k][k], pre[i][j] = k;			if(f[j][j] + f[i][j - 1] > f[i][j])				f[i][j] = f[j][j] + f[i][j - 1], pre[i][j] = j;		}	printf("%d\n", f[1][n]);	solve(1, n);	return 0;}