有n个村落分布在一条公路的沿线，为方便村民们就医，现打算在公路沿线修建一所医院。



　　由于各村落人数、年龄分布不同等原因，每个村落对医院的需求程度也不同。这里需求程度以一个非负的权值w表示：w越大，就医需求越大。对于一个选址方案，Σwi*di作为衡量其合理性的指标，其中wi和di分别表示第i个村落的权值和距离医院的距离，该指标越小，对应的选址就越优。请给出医院修建的最优位置。-There are n number of villages spread along a road, and for the convenience of the villagers for medical treatment, is now going to build a hospital along the road repair.



As a result of the number of villages, the age distribution of different reasons, the level of demand for hospital each village is different. The level of demand here in a non-negative weights w represents: w, the greater medical needs. For a site plan, Σwi* di as a measure of its reasonableness indicators, wi and di denote the i-th value　the right and　the hospital in the village, the smaller the index, the more excellent the corresponding location. Please give optimal locations hospital construction.