标签:lld int ace class zjoi name names logs font
复习斜率优化。
#include<cstdio> #include<iostream> #include<cstring> using namespace std; typedef long long LL; int list[1010000]; LL f[1010000],d[1010000],sp[1010000]; LL s[1010000],p[1010000],c[1010000]; double X(int j) { return double(f[j]+d[j]); } double Y(int j) { return double(sp[j]); } double slope(int j1,int j2) { return (X(j1)-X(j2))/(Y(j1)-Y(j2)); } int main() { int n; scanf("%d",&n); for(int i=1;i<=n;i++)scanf("%lld%lld%lld",&s[i],&p[i],&c[i]); d[0]=0;sp[0]=0; for(int i=1;i<=n;i++) { sp[i]=sp[i-1]+p[i]; d[i]=d[i-1]+p[i]*s[i]; } int head=1,tail=1; list[1]=0; for(int i=1;i<=n;i++) { while(head<tail&&slope(list[head],list[head+1])<double(s[i]))head++; int j=list[head]; f[i]=f[j]+c[i]+(sp[i-1]-sp[j])*s[i]-(d[i-1]-d[j]); while(head<tail&&slope(list[tail-1],list[tail])>slope(list[tail],i))tail--; list[++tail]=i; } printf("%lld\n",f[n]); return 0; }
标签:lld int ace class zjoi name names logs font
原文地址:http://www.cnblogs.com/AKCqhzdy/p/7799553.html