1600 旅行计划

单调队列优化DP

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
inline ll read()
{
    ll s=0;
    bool f=0;
    char ch=' ';
    while(!isdigit(ch))
    {
        f|=(ch=='-');
        ch=getchar();
    }
    while(isdigit(ch))
    {
        s=(s<<3)+(s<<1)+(ch^48);
        ch=getchar();
    }
    return (f)?(-s):(s);
}
#define R(x) x=read()
inline void write(ll x)
{
    if(x<0)
    {
        putchar('-');
        x=-x;
    }
    if(x<10)
    {
        putchar(x+'0');
        return;
    }
    write(x/10);
    putchar((x%10)+'0');
    return;
}
inline void writeln(ll x)
{
    write(x);
    putchar('\n');
    return;
}
#define W(x) write(x),putchar(' ')
#define Wl(x) writeln(x)
const int N=1000005;
int n,You[N<<1],Dis[N<<1],You1[N<<2],Dis1[N<<1],Oil[N<<1];
ll Sum[N<<1];
bool ans[N<<1];
struct Data
{
    ll Shuz;
    int Weiz;
}Ddq[N<<1];
int main()
{
    int i,Head,Tail;
    R(n);
    for(i=1;i<=n;i++)
    {
        You[i]=You[i+n]=read();
        Dis[i]=Dis[i+n]=read();
        Oil[i]=Oil[i+n]=You[i]-Dis[i];
    }
    Head=1; Tail=0;
    for(i=1;i<=n+n;i++)
    {
        Sum[i]=Sum[i-1]+Oil[i];
        while(Head<Tail&&Ddq[Head].Weiz<i-n+1) Head++;
        if(i>=n)
        {
            if(Ddq[Head].Shuz-Sum[i-n]<0) ans[i-n+1]=0;
            else ans[i-n+1]=1;
        }
        while(Head<=Tail&&Ddq[Tail].Shuz>Sum[i]) Tail--;
        Ddq[++Tail]=(Data){Sum[i],i};
    }
    for(i=1;i<=n;i++)
    {
        You1[i]=You[n-i+2];
        Dis1[i]=Dis[n-i+1];
        Oil[i]=Oil[i+n]=You1[i]-Dis1[i];
    }
    Head=1; Tail=0;
    for(i=1;i<=n+n;i++)
    {
        Sum[i]=Sum[i-1]+Oil[i];
        while(Head<Tail&&Ddq[Head].Weiz<i-n+1) Head++;
        if(i>=n)
        {
            if(Ddq[Head].Shuz-Sum[i-n]>=0)
            {
                (i==n)?(ans[1]=1):(ans[n-(i-n+1)+2]=1);
            }
        }
        while(Head<=Tail&&Ddq[Tail].Shuz>Sum[i]) Tail--;
        Ddq[++Tail]=(Data){Sum[i],i};
    }
    for(i=1;i<=n;i++)
    {
        (ans[i])?puts("TAK"):puts("NIE");
    }
    return 0;
}