Bzoj 1342: [Baltic2007]sound mute problem (monotone queue)

At first, I wrote a rmq and then t ...

Well, the positive solution is a monotone queue that maintains two monotone queues ...

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#include <bits/stdc++.h>#define REP (i, n) for (int i = 0; i < n; i++)#define CLR (x, C) memset (x, C, sizeof (x))using namespace std;const int MAXN = 1000009; int SEQ[MAXN], n, M, C;deque<int> mn, MX;vector<int> ans;int main () {freopen ("test.in", "R", stdin);freopen ("Test.out", "w", stdout);cin >> n >> m >> C;Rep (i, N) scanf ("%d", seq + i);ans.clear ();for (int i = n-1; ~i; i--) {if (!mn.empty () && Mn.front ()-I >= m) Mn.pop_front ();if (!mx.empty () && Mx.front ()-I >= m) Mx.pop_front ();while (!mn.empty () && seq[mn.back ()] >= seq[i]) mn.pop_back ();while (!mx.empty () && seq[mx.back ()] <= seq[i]) mx.pop_back ();Mn.push_back (i);Mx.push_back (i);if (i <= n-m && seq[mx.front ()]-Seq[mn.front ()] <= c)Ans.push_back (i + 1);}if (ans.size ())for (int i = Ans.size ()-1; ~i; i--) printf ("%d\n", Ans[i]);Elseputs ("NONE");return 0;}

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1342: [Baltic2007]sound mute problem time limit: 5 Sec Memory Limit: 162 MB
Submit: 725 Solved: 312
[Submit] [Status] [Discuss] Description Mute problem in digital recording, the sound is described by a sequence of numbers that represent air pressure, each of which is called a sample, and the interval between each sample is a certain amount of time. Many sound processing tasks require that the recorded sound be divided into a few non-silent segments separated by silence. To avoid dividing into too many or too few non-silent segments, muting is usually defined as: M-sampled sequences, where the difference between the maximum and minimum values sampled in the sequence does not exceed a specific threshold of C. Please write a program to detect the Silence in N samples. The first line of input has three integers n,m,c (1<= n<=1000000,1<=m<=10000, 0<=c<=10000), respectively, representing the total number of samples, the length of the mute, and the maximum allowable noise level in silence. The 2nd row n integer ai (0 <= ai <= 1,000,000) represents each sampled value of the sound, separated by a space between every two integers. Output lists all mute start positions I (I meet Max (A[i, ..., i+m−1]) −min (a[i, ..., i+m−1]) <= c), each line represents the starting position of a mute, in the order in which it appears. If there is no mute, the output is none. Sample Input7 2 0
0 1 1 2 3 2 2
Sample Output2
6
HINT

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Bzoj 1342: [Baltic2007]sound mute problem (monotone queue)