[{"sectionTitle":"题目描述","type":"Text","text":"给定一个具有 $N$ 个顶点的凸多边形，将顶点从 $1$ 至 $N$ 标号，每个顶点的权值都是一个正整数。将这个凸多边形划分成 $N-2$ 个互不相交的三角形，试求这些三角形顶点的权值乘积和至少为多少。","subType":"markdown"},{"sectionTitle":"输入格式","type":"Text","text":"输入第一行为顶点数 $N$\r\n\r\n第二行依次为顶点 $1$ 至顶点 $N$ 的权值。","subType":"markdown"},{"sectionTitle":"输出格式","type":"Text","text":"输出仅一行，为这些三角形顶点的权值乘积和的最小值。","subType":"markdown"},{"sectionTitle":"样例","type":"Sample","text":"","subType":"markdown","payload":["5\n121 122 123 245 231","12214884"]},{"sectionTitle":"数据范围与提示","type":"Text","text":"对于 $100\\%$ 的数据，有 $N\\le 50$，每个点权值小于 $10^9$。","subType":"markdown"}]