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#include#include #include using namespace std;int a[100010], t[100010];long long ans = 0;void merge_sort(int* a, int x, int y, int* t){ if (y - x > 1){ int m = x + (y - x) / 2; int p = x, q = m, i = x; merge_sort(a, x, m, t); merge_sort(a, m, y, t); while (p < m || q < y) if (q >= y || (p < m && a[p] < a[q])) t[i++] = a[p++]; else t[i++] = a[q++], ans += m - p; for (int j = x; j < y; j++) a[j] = t[j]; }}int main(){ int n; cin>>n; for (int i = 0; i < n; i++) scanf("%d", &a[i]); merge_sort(a, 0, n, t); cout<
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