mxqz

求助，复杂度正确O(n)，1WA2TLE

#include<bits/stdc++.h>
using namespace std;
#define int long long
int n,m,head,tail;
struct node{
    int tim,zhi;
}a[2000005];
signed main(){
    cin>>n>>m;
    head=1,tail=0;
    for(int i=1; i<=n; i++){
        int x;
        cin>>x;
        while(head<=tail&&a[tail].zhi>=x)
            tail--;  
        while(head<=tail&&a[head].tim<i-m)
            head++;
        if(i==1)
            cout<<"0\n";
        else
            cout<<a[head].zhi<<endl;
        a[++tail].zhi=x;
        a[tail].tim=i;
    }
    return 0;
}