func_code_string: #include <bits/stdc++.h>   using namespace std;   const int MAX = 1e6;   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     int n;     cin >> n;     long long a[n + 2];     a[0] = 0;     long long sum = 0;     for (int i = 1; i <= n; i++) {       cin >> a[i];       if (a[i] > a[i - 1])         sum += (a[i] - a[i - 1]) * (n - a[i] + 1);       else if (a[i] < a[i - 1])         sum += a[i] * (a[i - 1] - a[i]);     }     cout << sum << endl;   }   