#include<iostream>#include<cstring>#include<cstdio>#include<algorithm>#include<string>#include<map>#include<cmath>#include<vector>#include<set>using namespace std;int f_min(int x,int y){return x<y?x:y;}int f_max(int x,int y){return x>y?x:y;}int f_abs(int x){return x<0?-x:x;}int N,num[105],ans[105];void get_data(){int i;scanf("%d",&N);for(i=0;i<N;i++)scanf("%d",&num[i]);}void run(){int i,res=0;for(i=0;i<N;i++)ans[i]=num[i];for(i=1;i<N-1;i++){if(ans[i]<ans[i-1]&&num[i]<ans[i+1]){ans[i]=f_min(ans[i-1],ans[i+1]);}if(ans[i]>ans[i-1]&&ans[i]>ans[i+1]){ans[i]=f_max(ans[i-1],ans[i+1]);}}for(i=0;i<N;i++)res+=f_abs(ans[i]-num[i]);for(i=1;i<N;i++)res+=f_abs(ans[i-1]-ans[i]);printf("%dn",res);}int main(){get_data();run();return 0;}
