[BZOJ3437] 小P的牧场 && 斜率优化

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如果你搞了前面的斜率优化的题那么这道题应该不算难考的时候脑残推错了说不出话来 BZOJ数据显示也是坑明明100W 后面加个，0 关键是我开1000W会直接T 坑

#include<cstdio>using namespace std;typedef long long LL;const int MAXN = 1000000;LL d[MAXN+10], Q[MAXN+10], Cost[MAXN+10], F, R, S[MAXN+10], T[MAXN+10];int n, m;inline LL Slope_U(int i, int j){return d[i] + T[i] - (d[j] + T[j]);}inline LL Slope_D(int i, int j){return S[i] - S[j];}inline LL read(){     LL x=0,f=1;char ch=getchar();while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}while(ch>='0'&&ch<='9'){x=10*x+ch-'0';ch=getchar();}return x*f;}int main(){scanf("%d", &n);for(int i = 1; i <= n; i++) Cost[i] = read();for(int i = 1; i <= n; i++) {LL x = read();S[i] = S[i-1] + x;T[i] = T[i-1] + x * i;}F = R = Q[0] = 0;Q[R++] = 0;for(int i = 1; i <= n; i++){while(F < R-1 && Slope_U(Q[F+1], Q[F]) <= Slope_D(Q[F+1], Q[F]) * i)F++;d[i] = d[Q[F]] + Cost[i] + i * (S[i] - S[Q[F]]) - (T[i] - T[Q[F]]); while(F < R-1 && Slope_U(Q[R-1], Q[R-2]) * Slope_D(i, Q[R-1]) >= Slope_U(i, Q[R-1]) * Slope_D(Q[R-1], Q[R-2]))R--;Q[R++] = i;}printf("%lld\n", d[n]);}/*42 4 2 43 1 4  2*/

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