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#pragma comment(linker, "/STACK:102400000,102400000") #include <algorithm> #include <iostream> #include <cstdlib> #include <cstring> #include <sstream> #include <vector> #include <cstdio> #include <bitset> #include <string> #include <cmath> #include <deque> #include <queue> #include <stack> #include <map> #include <set> using namespace std; typedef long long ll; const double pi = acos(-1.0); const int eps = 1e-10; const int mod = 1e9 + 7; const int INF = 0x3f3f3f3f; const int maxn = 1e5 + 5;
ll a[maxn]; struct node { ll sum; ll lazy; } A[maxn << 2];
void build(int u, int l, int r) { A[u].lazy = 0; if (l == r) { A[u].sum = 0; return; } int mid = (l + r) / 2; build(2 * u, l, mid); build(2 * u + 1, mid + 1, r); A[u].sum = A[2 * u].sum + A[2 * u + 1].sum; }
void pushdown(int u, int l,int r) { if (A[u].lazy == 0) return ; int mid = (l + r) / 2; A[u * 2].sum += A[u].lazy * (mid - l + 1); A[u * 2 + 1].sum += A[u].lazy * (r - mid); A[u * 2].lazy += A[u].lazy; A[u * 2 + 1].lazy += A[u].lazy; A[u].lazy = 0; }
void add(int u, int sl, int sr, int l, int r, ll k) { if (l > sr || r < sl) return ; if (l <= sl && r >= sr) { A[u].sum += k * (sr - sl + 1); A[u].lazy += k; return ; } pushdown(u, sl, sr); int mid = (sl + sr) / 2; add(2 * u, sl, mid, l, r, k); add(2 * u + 1, mid + 1, sr, l, r, k); A[u].sum = A[u * 2].sum + A[u * 2 + 1].sum; return ; }
ll query(int u, int sl, int sr, int l, int r) { if (l > sr || r < sl) return 0; if (l <= sl && r >= sr) return A[u].sum; pushdown(u, sl, sr); int mid = (sl + sr) / 2; return (query(2 * u, sl, mid, l, r) + query(2 * u + 1, mid + 1, sr, l, r)); }
int t, n, q, x, y, k; char c; int main() {
while (~scanf("%d", &n)) { build(1, 1, n - 1); ll temp = 0; for (int i = 1; i <= n; i++) { scanf("%lld", &a[i]); temp += query(1, 1, n - 1, a[i], n - 1); add(1, 1, n - 1, a[i], a[i], 1); }
int ans = temp, sum = temp; for (int i = 1; i <= n - 1; i++) { sum = sum - a[i] + (n - 1 - a[i]); ans = min(ans, sum); } printf ("%d\n", ans); }
return 0; }
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