滑动窗口

POJ2823

#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <iostream>
#include <algorithm>
using namespace std;
#define ll long long
#define re register
const int N=1e6+10;
inline void read(int &a)
{
    a=0;
    int d=1;
    char ch;
    while(ch=getchar(),ch>'9'||ch<'0')
        if(ch=='-')
            d=-1;
    a=ch^48;
    while(ch=getchar(),ch>='0'&&ch<='9')
        a=(a<<3)+(a<<1)+(ch^48);
    a*=d;
}
inline void write(int x)
{
    if(x<0)
        putchar(45),x=-x;
    if(x>9)
        write(x/10);
    putchar(x%10+'0');
}
struct note
{
    int pos,val;
}qma[N],qmi[N];
int ma[N],mi[N],cnt=0;
int main()
{
    int n,m;
    while(~scanf("%d %d",&n,&m))
    {
        int l1,r1,l2,r2;
        l1=r1=l2=r2=1;
        cnt=0;
        for(re int i=1;i<=m;i++)
        {
            int x;
            read(x);
            while(l1<r1&&qmi[r1-1].val>=x)
                r1--;
            qmi[r1].val=x;
            qmi[r1++].pos=i;

            while(l2<r2&&qma[r2-1].val<=x)
                r2--;
            qma[r2].val=x;
            qma[r2++].pos=i;
        }
        for(re int i=m+1;i<=n;i++)
        {
            ma[++cnt]=qma[l2].val;
            mi[cnt]=qmi[l1].val;
            int x;
            read(x);

            while(l1<r1&&i-qmi[l1].pos>=m)
                l1++;
            while(l1<r1&&qmi[r1-1].val>=x)
                r1--;
            qmi[r1].val=x;
            qmi[r1++].pos=i;

            while(l2<r2&&i-qma[l2].pos>=m)
                l2++;
            while(l2<r2&&qma[r2-1].val<=x)
                r2--;
            qma[r2].val=x;
            qma[r2++].pos=i;
        }
        ma[++cnt]=qma[l2].val;
        mi[cnt]=qmi[l1].val;
        for(re int i=1;i<cnt;i++)
            write(mi[i]),putchar(' ');
        write(mi[cnt]);putchar('
');
        for(re int i=1;i<cnt;i++)
            write(ma[i]),putchar(' ');
        write(ma[cnt]),putchar('
');
    }
    return 0;
}