Maximum value minus the minimum number of sub-arrays that are less than or equal to num

"description":

This article is a C + + recurrence of the topic " maximum value minus minimum value less than or equal to num number of sub-arrays " in the first chapter of the Programmer's Interview code guide by Zhoecheng.

This article only contains the problem description, the implementation of C + + code and simple ideas, not including the explanation, the specific problem analysis please refer to the original book.

Thank Zhoecheng teacher for his support.

"title":

Given the array arr and integer num, the total number of word groups returned satisfies the following conditions:

Max (ARR[I...J])-min (ARR[I...J]) <= num

Max (ARR[I...J]) represents the maximum value in the word group ARR[I...J], and Min (ARR[I...J]) represents the minimum value in the Subarray ARR[I...J].

"ideas":

1, if ARR[I...J] satisfies the condition, then its sub-array will also satisfy the condition;

2, if ARR[I...J] dissatisfaction group conditions, then contains ARR[I...J] array are not satisfied with the conditions;

"Compile environment":

CentOS6.7 (x86_64)

GCC 4.4.7

"Implementation":

Implementing and testing the code:

1 /*2 * File name: GetSatisfiedSubArrNum.cpp3  *4 * Summary: Find the number of sub-arrays that meet the criteria5  */6 7#include <iostream>8#include <deque>9 Ten using namespacestd; One  A intGetnum (intArr[],intLenintnum) - { -     if(NULL = = Arr | |0>=len) the         return 0; -deque<int> qmin;//the first data of qmin is always the location of the smallest data in the current array -deque<int> Qmax;//the first data of Qmax is always the position of the largest data in the current array -      +     intI0), J (0), Res (0); -      while(I <len) +     { A          while(I <len) at         { -              while(!qmin.empty () && Arr[qmin.front ()] >=Arr[j]) - Qmin.pop_back (); - Qmin.push_back (j); -  -              while(!qmax.empty () && Arr[qmax.front () <=Arr[j]]) in Qmax.pop_back (); - Qmax.push_back (j); to  +             if(Arr[qmax.front ()]-Arr[qmin.front ()] >num) -                  Break;// theJ + +; *         } $Res + = J-i;//record the number of word groups that meet the requirements in the current sequencePanax Notoginseng          -         if(Qmin.front () = =i) the Qmin.pop_front (); +         if(Qmax.front () = =i) A Qmax.pop_front (); thei++;//Move Down +     } -     returnRes; $ } $  - intMain () - { the     intA[] = {3,2,5,1,4,7,8,6}; -cout <<"The number of sub arrays to meet the requirements is:"<< Getnum (A,8,4) <<Endl;Wuyi  the     return 0; -}

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Note:

Reprint please indicate the source;

Reprint please indicate source idea from Zhoecheng Teacher's "Programmer Code Interview Guide"

Maximum value minus the minimum number of sub-arrays that are less than or equal to num