int main() { int W, L; cin >> W; cin >> L; vector<int> H; while (L) { int a; cin >> a; a = 100 - a; H.push_back(a); L--; } int max=H[H.size()-1]; int sum = 0; int base = 1 * 1 * W; for (int i = H.size() - 2; i >= 0; i--) { if (H[i] >= max) { max = H[i]; } else { sum = sum + base * (max - H[i]); } } cout << sum << endl; }