HDU 3530Subsequence(单调队列)

/*
*/
#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstdlib>
#include<ctime>
#include<cstring>
#include<algorithm>
#include<vector>
#define Pair pair<int, int> 
#define MP(x, y) make_pair(x, y)
#define fi first
#define se second
using namespace std;
const int MAXN = 1e6 + 10;
const double eps = 1e-10, Dlt = 0.97, INF = 1e9 + 7;
inline int read() {
    char c = getchar(); int x = 0, f = 1;
    while(c < '0' || c > '9') {if(c == '-') f = -1; c = getchar();}
    while(c >= '0' && c <= '9') x = x * 10 + c - '0', c = getchar();
    return x * f;
}
int N, x, y, a[MAXN];
int h1, t1, q1[MAXN], h2, t2, q2[MAXN];
int main() {
    while(scanf("%d %d %d", &N, &x, &y) != EOF) {
        int ans = 0, pre = 0;
        h1 = h2 = 1; t1 = t2 = 0;
        for(int i = 1; i <= N; i++) {
            a[i] = read();
            while(h1 <= t1 && a[i] > a[q1[t1]]) t1--;//鍖洪棿鏈€澶у€?
            while(h2 <= t2 && a[i] < a[q2[t2]]) t2--;//鍖洪棿鏈€灏忓€?
            q1[++t1] = i;
            q2[++t2] = i;
            while(h1 <= t1 && h2 <= t2 && a[q1[h1]] - a[q2[h2]] > y) {
                if(q1[h1] < q2[h2]) pre = q1[h1], h1++;
                else pre = q2[h2], h2++;
            }
            if(h1 <= t1 && h2 <= t2 && (a[q1[h1]] - a[q2[h2]] >= x)) 
                ans = max(ans, i - pre); 
        }
        printf("%d\n", ans);
    }
    return 0;
}
/*
5 3 3
1 2 3 4 5
*/