#include #include #include using std::cin; using std::cout; const char endl = '\n'; const int N = 105, M = 2005, INF = 0x3f3f3f3f; int n, s, t, a[N], sum, avg, cost; // Graph int idx, head[N], ver[M << 1], next[M << 1]; std::pair edge[M << 1]; // void add(int u, int v, int flow, int cost) { next[idx] = head[u]; ver[idx] = v; edge[idx] = std::make_pair(flow, cost); head[u] = idx++; } // Dinic int dist[N]; bool vis[N]; bool spfa() { std::memset(vis, 0x00, sizeof(vis)); std::memset(dist, 0x3f, sizeof(dist)); std::queue q; q.push(s); dist[s] = 0; vis[s] = true; while (!q.empty()) { int u = q.front(); q.pop(); vis[u] = false; for (int i = head[u]; ~i; i = next[i]) { int v = ver[i], c = edge[i].first, w = edge[i].second; if (dist[v] > dist[u] + w && c > 0) { dist[v] = dist[u] + w; if (!vis[v]) { q.push(v); vis[v] = true; } } } } return dist[t] != INF; } int dinic(int u, int limit) { if (u == t) return limit; int flow = 0; vis[u] = true; for (int i = head[u]; ~i && flow < limit; i = next[i]) { int v = ver[i], c = edge[i].first, w = edge[i].second; if (dist[v] == dist[u] + w && c && !vis[v]) { int k = dinic(v, std::min(c, limit - flow)); if (!k) dist[v] = INF; edge[i].first -= k; edge[i ^ 1].first += k; flow += k; cost += k * w; } } vis[u] = false; return flow; } int main() { std::ios::sync_with_stdio(false); memset(head, 0xff, sizeof(head)); cin >> n; for (int i = 1; i <= n; i++) { cin >> a[i]; sum += a[i]; } avg = sum / n; s = 0, t = n + 1; for (int i = 1; i <= n; i++) { if (a[i] - avg > 0) { add(s, i, a[i] - avg, 0); add(i, s, 0, 0); } else if (a[i] - avg < 0) { add(i, t, avg - a[i], 0); add(t, i, 0, 0); } } for (int i = 1; i <= n; i++) { if (i > 1) { add(i, i - 1, INF, 1); add(i - 1, i, 0, -1); } if (i < n) { add(i, i + 1, INF, 1); add(i + 1, i, 0, -1); } } add(1, n, INF, 1); add(n, 1, 0, -1); add(n, 1, INF, 1); add(1, n, 0, -1); while (spfa()) dinic(s, INF); cout << cost << endl; return 0; }