#include <iostream>                                                                                             
#include <algorithm>                                                                                            
#include <cmath>                                                                                                
                                                                                                                
using namespace std;                                                                                            
                                                                                                                
int a[100000];                                                                                                  
                                                                                                                
int main(void){                                                                                                 
    int n, k;                                                                                                   
                                                                                                                
    cin >> n >> k;                                                                                              
                                                                                                                
    int id = -1;                                                                                                
                                                                                                                
    for (int i = 0; i < n; i++){                                                                                
        cin >> a[i];                                                                                            
        if (id == -1 && a[i] >= 0)                                                                              
            id = i;                                                                                             
                                                                                                                
    }                                                                                  
                         if (id == -1)
id = n;
                                                                                        
                                                                                                                
    int m = 1e9;                                                                                                
                                                                                                                
                                                                                                                
    for (int i = 0; i <= k; i++){                                                                               
        if (id >= k - i && i <= n - id){                                                                        
            if (i == 0){                                                                                        
                m = min(m, abs(a[id - k]));                                                                     
            }                                                                                                   
            else if (i == k){                                                                                   
                m = min(m, abs(a[id+k - 1]));                                                                   
            }                                                                                                   
            else {                                                                                              
                m = min(m, min(2*abs(a[id+i-1]) + abs(a[id-k+i]), abs(a[id+i-1]) + 2*abs(a[id-k+i])));          
            }                                                                                                   
        }                                                                                                       
    }                                                                                                           
                                                                                                                
    cout << m << endl;                                                                                          
}                                                                                                               

Measured memory_bytes: 640