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| using namespace std; | |
| using LL = long long; | |
| struct fenwick { // For 1-based indices. | |
| vector<LL> a, t; | |
| fenwick(int N) : a(N + 1), t(N + 1) {} | |
| LL sum(int hi) const { | |
| LL res = 0; | |
| for (; hi > 0; hi -= hi & -hi) { | |
| res += t[hi]; | |
| } | |
| return res; | |
| } | |
| void inc(int i, LL x) { | |
| a[i] += x; | |
| for (; i < (int)t.size(); i += i & -i) { | |
| t[i] += x; | |
| } | |
| } | |
| LL at(int i) const { return a[i]; } | |
| LL sum(int lo, int hi) const { return sum(hi) - sum(lo - 1); } | |
| void set(int i, LL x) { inc(i, x - a[i]); } | |
| }; | |
| template <typename Predicate> | |
| int binary_search_last_true(int lo_incl, int hi_excl, Predicate pred) { | |
| int mid, lo = lo_incl, hi = hi_excl - 1; | |
| while (lo < hi) { | |
| mid = lo + (hi - lo + 1) / 2; | |
| if (pred(mid)) { | |
| lo = mid; | |
| } else { | |
| hi = mid - 1; | |
| } | |
| } | |
| return pred(lo) ? lo : hi_excl; | |
| } | |
| LL solve() { | |
| int N, M; | |
| cin >> N >> M; | |
| auto rev = [=](int i) -> int { return N - i + 1; }; | |
| fenwick Tv_fwd(N), Ti_fwd(N), Tv_rev(N), Ti_rev(N); | |
| for (int i = 1, a; i <= N; i++) { | |
| cin >> a; | |
| Tv_fwd.set(i, a == 2); | |
| Ti_fwd.set(i, a == 2 ? i : 0); | |
| Tv_rev.set(rev(i), a == 2); | |
| Ti_rev.set(rev(i), a == 2 ? i : 0); | |
| } | |
| LL ans = 0; | |
| for (int i = 0, x, y, z; i < M; i++) { | |
| cin >> x >> y >> z; | |
| Tv_fwd.set(x, y == 2); | |
| Ti_fwd.set(x, y == 2 ? x : 0); | |
| Tv_rev.set(rev(x), y == 2); | |
| Ti_rev.set(rev(x), y == 2 ? x : 0); | |
| int L2cnt = Tv_fwd.sum(1, z), H2cnt = Tv_fwd.sum(z + 1, N); | |
| int sumL = 1 * (z - L2cnt) + 2 * L2cnt; | |
| int sumH = 1 * (N - z - H2cnt) + 2 * H2cnt; | |
| if (sumL == sumH) { | |
| continue; | |
| } | |
| auto getQ = [&]( | |
| const fenwick &Tv, const fenwick &Ti, int d, int z, bool is_rev | |
| ) -> LL { | |
| int req2s = d / 2, tgt2s = Tv.sum(1, z) + req2s; | |
| if ( | |
| d % 2 == 1 || // Can't reduce d by an odd number with swaps. | |
| tgt2s > z || // Not enough room to fit all the 2's to make d = 0. | |
| req2s > Tv.sum(z + 1, N) // Not enough 2's from H to move over to L. | |
| ) { | |
| return -1; | |
| } | |
| // Assuming sumL < sumH, check that a choice of s will make sumL >= sumH | |
| // if we fill a A[s..z] by shifting 2's from A[(z+1)..N] leftwards, all | |
| // without touching the 2's in A[1..(s-1)]. | |
| int s = binary_search_last_true(1, z + 1, [&](int s) { | |
| // On the domain s=1..z, this predicate yields a pattern 1111000, as | |
| // we'll need force sufficiently many 2's in A[s..z] to hit the target | |
| // number of 2s required to make sumL = sumH. | |
| return Tv.sum(1, s - 1) + (z - s + 1) >= tgt2s; | |
| }); | |
| assert(s <= z); | |
| int c = z - s + 1; | |
| // Now compute the total cost of shifting the 2s from the range s..t | |
| // leftwards to fill the indices s..z. | |
| int t = 1 + binary_search_last_true(s, N + 1, [&](int t) { | |
| // On the domain t=s..N, this predicate yields a pattern 1111000, as | |
| // we'll need to choose sufficiently large t for there to be enough 2s. | |
| return Tv.sum(s, t) < c; | |
| }); | |
| assert(t <= N); | |
| // Q_i = (sum of final indices of 2s) - (sum of initial indices of 2s). | |
| if (is_rev) { | |
| return (LL)c*(rev(s) + rev(z))/2 - Ti.sum(s, t); | |
| } | |
| return Ti.sum(s, t) - (LL)c*(s + z)/2; | |
| }; | |
| if (sumL < sumH) { | |
| ans += getQ(Tv_fwd, Ti_fwd, sumH - sumL, z, false); | |
| } else { | |
| ans += getQ(Tv_rev, Ti_rev, sumL - sumH, rev(z) - 1, true); | |
| } | |
| } | |
| return ans; | |
| } | |
| int main() { | |
| ios_base::sync_with_stdio(false); | |
| cin.tie(nullptr); | |
| int T; | |
| cin >> T; | |
| for (int t = 1; t <= T; t++) { | |
| cout << "Case #" << t << ": " << solve() << endl; | |
| } | |
| return 0; | |
| } | |