#include <cstdio> #include <algorithm> using namespace std; const int maxn = 110; const int INF = 214748364; int a[maxn<<1]; int maxdp[maxn<<1][maxn<<1], mindp[maxn<<1][maxn<<1]; int sum[maxn<<1]; int main() { int n; scanf("%d", &n); int i, len, l, r, k; for(i = 1; i <= n; ++i) { scanf("%d", &a[i]); a[n+i]=a[i];//环断链 } sum[0] = 0; for(i = 1; i <= 2*n; ++i) sum[i]=sum[i-1]+a[i];//预处理前缀和 for(len = 2; len <= n; ++len)//枚举区间长度 for(l = 1; l+len-1 < 2*n; ++l)//枚举区间起点 { r = l+len-1;//区间终点 maxdp[l][r] = 0;//在这里初始化 mindp[l][r] = INF; for(k = l; k < r; ++k)//枚举断点 { maxdp[l][r] = max(maxdp[l][r], maxdp[l][k]+maxdp[k+1][r]+sum[r]-sum[l-1]); mindp[l][r] = min(mindp[l][r], mindp[l][k]+mindp[k+1][r]+sum[r]-sum[l-1]); } } int maxans = 0; int minans = INF; for(i = 1; i <= n; ++i) { maxans = max(maxans, maxdp[i][i+n-1]); minans = min(minans, mindp[i][i+n-1]); } printf("%d\n%d\n", minans, maxans); return 0; }
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