BZOJ 3831 [Poi2014]Little Bird【单调队列优化dp

#include<bits/stdc++.h>
#define MAXN 1000005
using namespace std;	int n,q,k;
inline int read(){
register char ch = getchar();
register int rtn = 0;
while(!isdigit(ch))	ch = getchar();
while(isdigit(ch))	rtn = rtn*10 + ch - '0' , ch = getchar();
return rtn;
}
int h[MAXN];
int f[MAXN];
int que[MAXN] , l , r;

int main(){
freopen("1.in","r",stdin);
n = read();
for(int i=1;i<=n;++i)	h[i] = read();
q = read();
while(q--){
k = read();
l = r = que[1] = 1;
f[1] = 0;
for(int i=2;i<=n;++i){
while(que[l]<i-k)	++l;
f[i] = f[que[l]] + (h[i]>=h[que[l]]);
while(r>=l&&f[i]<f[que[r]])	--r;
while(r>=l&&f[i]==f[que[r]]&&h[i]>h[que[r]])	--r;
que[++r] = i;
}
printf("%d\n",f
);
}
return 0;
}