#include using namespace std; int n; int niza[100005]; int frog[100005]; int rec(int frog_at) { if(frog_at == n - 1) { return 0; } if(frog[frog_at] != -1) { return frog[frog_at]; } int result = 2e9; if(frog_at + 1 < n) { result = min(result, rec(frog_at + 1) + abs(niza[frog_at] - niza[frog_at + 1])); } if(frog_at + 2 < n) { result = min(result, rec(frog_at + 2) + abs(niza[frog_at] - niza[frog_at + 2])); } return frog[frog_at] = result; } int main() { cin >> n; for(int i = 0; i < n; i++) { cin >> niza[i]; } for(int i = 0; i <= n; i++) { frog[i] = -1; } cout<< rec(0) << endl; return 0; } /* rec(0) = MIN(rec(1) + 20 || rec(2) + 30) = MIN(30, 50) = 30 rec(1) = MIN(rec(2) + 10 || rec(3) + 10) = Min(30, 10) = 10 rec(2) = MIN(rec(3) + 20) = 20 rec(3) = 0 **/