#include <cmath>
#include <cstdio>
#include <climits>
#include <algorithm>

short n;
int tmp,ans = 0,a[SHRT_MAX + 5];

int f(int x){
    
    int cnt = INT_MAX;
    
    if (x == 1) return a[1];
    for (int i = 1;i < x;i++)
        cnt = std::min(abs(a[i] - a[x]),cnt);
    
    return cnt;
}

int main(){
    
    scanf("%hd",&n);
    for (int i = 1;i <= n;i++) scanf("%d",&a[i]);
    for (int i = 1;i <= n;i++) ans += f(i);
    printf("%d",ans);
    
    return 0;
}