【AI PC端算法优化】五，常量阶最大值最小值滤波算法

#include <bits/stdc++.h>
using namespace std;
const int maxn = 110;
deque <int> U, L;
int maxval[maxn], minval[maxn];

int main(){
    int a[10] = {0, 1, 9, 8, 2, 3, 7, 6, 4, 5};
    int w = 3;
    for(int i = 1; i < 10; i++){
        if(i >= w){
            maxval[i - w] = a[U.size() > 0 ? U.front() : i-1];
            minval[i - w] = a[L.size() > 0 ? L.front() : i-1];
        }
        if(a[i] > a[i-1]){
            L.push_back(i - 1);
            if(i == w + L.front()) L.pop_front();
            while(U.size() > 0){
                if(a[i] <= a[U.back()]){
                    if(i == w + U.front()) U.pop_front();
                    break;
                }
                U.pop_back();
            }
        }
        else{
            U.push_back(i-1);
            if(i == w + U.front()) U.pop_front();
            while(L.size() > 0){
                if(a[i] >= a[L.back()]){
                    if(i == w + L.front()) L.pop_front();
                    break;
                }
                L.pop_back();
            }
        }
    }
    maxval[10 - w] = a[U.size() > 0 ? U.front() : 9];
    minval[10 - w] = a[L.size() > 0 ? L.front() : 9];
    for(int i = 0; i <= 10 - w; i++){
        printf("Min index %d is: %d\n", i, minval[i]);
        printf("Max index %d is: %d\n", i, maxval[i]);
    }
    return 0;
}