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| 1 | +#include <iostream> |
| 2 | +#include <vector> |
| 3 | +#include <algorithm> |
| 4 | + |
| 5 | +#define all(v) (v).begin(), (v).end() |
| 6 | +using namespace std; |
| 7 | + |
| 8 | +const int MAX_N = 5005; |
| 9 | +int prefix_smaller[MAX_N][MAX_N], suffix_smaller[MAX_N][MAX_N]; |
| 10 | + |
| 11 | +void solve() |
| 12 | +{ |
| 13 | + int no_of_elements; |
| 14 | + cin >> no_of_elements; |
| 15 | + |
| 16 | + vector <int> A(no_of_elements + 1); |
| 17 | + vector <int> index(no_of_elements + 1); |
| 18 | + for(int i = 1; i <= no_of_elements; i++) |
| 19 | + { |
| 20 | + cin >> A[i]; |
| 21 | + |
| 22 | + index[A[i]] = i; |
| 23 | + } |
| 24 | + |
| 25 | + for(int b = 1; b <= no_of_elements; b++) |
| 26 | + { |
| 27 | + for(int c = b + 1; c <= no_of_elements; c++) |
| 28 | + { |
| 29 | + prefix_smaller[b][c] = suffix_smaller[b][c] = 0; |
| 30 | + } |
| 31 | + } |
| 32 | + |
| 33 | + vector <int> prefix_insertions(no_of_elements + 1, 0); |
| 34 | + for(int element = 1; element <= no_of_elements; element++) |
| 35 | + { |
| 36 | + for(int i = index[element]; i <= no_of_elements; i++) |
| 37 | + { |
| 38 | + prefix_insertions[i]++; |
| 39 | + } |
| 40 | + |
| 41 | + for(int c = index[element], b = 1; b < c; b++) |
| 42 | + { |
| 43 | + prefix_smaller[b][c] = prefix_insertions[b - 1]; |
| 44 | + } |
| 45 | + |
| 46 | + for(int b = index[element], c = b + 1; c <= no_of_elements; c++) |
| 47 | + { |
| 48 | + suffix_smaller[b][c] = prefix_insertions[no_of_elements] - prefix_insertions[c]; |
| 49 | + } |
| 50 | + } |
| 51 | + |
| 52 | + long long answer = 0; |
| 53 | + for(int b = 2; b + 2 <= no_of_elements; b++) |
| 54 | + { |
| 55 | + for(int c = b + 1; c + 1 <= no_of_elements; c++) |
| 56 | + { |
| 57 | + long long no_of_a = prefix_smaller[b][c], no_of_d = suffix_smaller[b][c]; |
| 58 | + answer += no_of_a*no_of_d; |
| 59 | + } |
| 60 | + } |
| 61 | + |
| 62 | + cout << answer << "\n"; |
| 63 | +} |
| 64 | + |
| 65 | +int main() |
| 66 | +{ |
| 67 | + ios_base::sync_with_stdio(false); |
| 68 | + cin.tie(NULL); |
| 69 | + |
| 70 | + int no_of_test_cases; |
| 71 | + cin >> no_of_test_cases; |
| 72 | + |
| 73 | + while(no_of_test_cases--) |
| 74 | + solve(); |
| 75 | + |
| 76 | + return 0; |
| 77 | +} |
| 78 | + |
| 79 | + |
| 80 | + |
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