Description
An array of size
N≤106 is given to you. There is a sliding window of size
kWhich is moving from the very left of the array to the very right. can only see the
kNumbers in the window. Each of the sliding window moves rightwards by one position. Following is an example:
The array is[1 3-1-3 5 3 6 7], and
kis 3.
Window Position |
Minimum Value |
Maximum Value |
[1 3-1]-3 5 3 6 7 |
-1 |
3 |
1 [3-1-3] 5 3 6 7 |
-3 |
3 |
1 3 [-1-3 5] 3 6 7 |
-3 |
5 |
1 3-1 [-3 5 3] 6 7 |
-3 |
5 |
1 3-1-3 [5 3 6] 7 |
3 |
6 |
1 3-1-3 5 [3 6 7] |
3 |
7 |
Your task is to determine the maximum and minimum values in the sliding window at each position.
Input
The input consists of the lines. The first line contains integers
Nand
kWhich is the lengths of the array and the sliding window. There is
NIntegers in the second line.
Output
There is lines in the output. The first line gives the minimum values in the windows at each position, from left to right, respectively. The second line gives the maximum values.
Sample Input
8 31 3-1-3 5 3 6 7
Sample Output
-1-3-3-3 3 33 3 5 5 6 7
Source
POJ monthly--2006.04.28, Ikki
Test Instructions:given a sequence of long n, ask the minimum and maximum of all the cases in the series with a length of K.
Ideas:Seniors Teach the RMQ solution, St version of the essence is DP, than do not understand DP before, now feel good understanding more. In addition, you can use segment tree solutions. Note the Log table first.
1#include <stdio.h>2#include <algorithm>3 //#define LOG[I] = (I & (i-1))? LOG[I-1]: log[i-1] + 14 #defineMAXX 12345675#include <vector>6 using namespacestd;7 8 intA[maxx];9 intdp1[maxx][ A];Ten intLog[maxx]; One A voidInitintN) - { -log[1] =0; the for(intI=2; i<=n; i++) -log[i]= (i& (i-1))? log[i-1]:log[i-1]+1; - } - + intST (intLintRinti) - { + intk=log[r-l+1]; A if(i==1) at returnMax (dp1[l][k],dp1[r-(1<<K) +1][k]); - if(i==0) - returnMin (dp1[l][k],dp1[r-(1<<K) +1][k]); - } - intMain () - { in intN, K; - to while(~SCANF ("%d%d", &n, &k)) + { - intI, J; the init (n); * for(i=1; i<=n; i++) $ {Panax Notoginsengscanf"%d", &a[i]); -dp1[i][0]=A[i]; the } + for(j=1; j<= -; J + +) A { the for(i=1; i<=n; i++) + { - if(I+ (1<<J)-1>N) $ Break; $Dp1[i][j]=min (dp1[i][j-1], dp1[i+ (1<< (J-1))][j-1]); - } - } the for(i=1; i<=n-k+1; i++) - {Wuyi if(i!=1) theprintf" "); -printf"%d", ST (i,i+k-1,0)); Wu } - ////// About $ for(i=1; i<=n; i++) - { -dp1[i][0]=A[i]; - for(j=1; j<= -; J + +) Adp1[i][j]=0; + } the for(j=1; j<= -; J + +) - { $ for(i=1; i<=n; i++) the { the if(I+ (1<<J)-1>N) the Break; theDp1[i][j]=max (dp1[i][j-1], dp1[i+ (1<< (J-1))][j-1]); - } in } theprintf"\ n"); the for(i=1; i<=n-k+1; i++) About { the if(i!=1) theprintf" "); theprintf"%d", ST (i,i+k-1,1)); + } -printf"\ n"); the }Bayi}
POJ 2823 Sliding Window ST RMQ