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斜率优化DP

斜率优化DP

斜率优化DP

斜率优化DPBZOJ题目传送门洛谷题目传送门先把方差推一下：KaTeX parse error: No such environment: align at position 8: \begin{̲a̲l̲i̲g̲n̲}̲vm^2&=m\sum(x_…∑xi\sum x_i∑xi​是个定值不用管，我们只要维护∑xi2\sum x_i^2∑xi2​就好了。设f[i][j]f[...

斜率优化BZOJ题目传送门洛谷题目传送门设f[i]f[i]f[i]为前iii个工厂且在iii建仓库的最小代价。那么有f[i]=min{f[j]+c[i]+∑k=jip[k]∗(X[i]−X[k])}f[i]=min\{f[j]+c[i]+\sum_{k=j}^ip[k]*(X[i]-X[k])\}f[i]=min{f[j]+c[i]+∑k=ji​p[k]∗(X[i]−X[k])}。因为第nn...