diff --git "a/khj20006/202511/29 BOJ P4 \354\270\240\353\260\224\353\251\224\352\260\200\354\227\220\354\213\234.md" "b/khj20006/202511/29 BOJ P4 \354\270\240\353\260\224\353\251\224\352\260\200\354\227\220\354\213\234.md" new file mode 100644 index 00000000..83a066b0 --- /dev/null +++ "b/khj20006/202511/29 BOJ P4 \354\270\240\353\260\224\353\251\224\352\260\200\354\227\220\354\213\234.md" @@ -0,0 +1,90 @@ +```cpp +#include +using namespace std; + +struct SegmentTree { + vector> tree; + + pair mrg(pair &a, pair &b) { + int mx1 = 0, mx2 = 0; + mx1 = max(a.first, b.first); + if (mx1 == a.first) mx2 = max(a.second, b.first); + else mx2 = max(a.first, b.second); + return { mx1, mx2 }; + } +public: + SegmentTree(int sz) { + tree.resize(sz * 4); + } + + void upt(int s, int e, int i, int v, int n) { + if (s == e) { + tree[n].first += v; + return; + } + int m = (s + e) >> 1; + if (i <= m) upt(s, m, i, v, n << 1); + else upt(m + 1, e, i, v, n << 1 | 1); + tree[n] = mrg(tree[n << 1], tree[n << 1 | 1]); + } +}; + +int N; +SegmentTree* segX = new SegmentTree(1000001); +SegmentTree* segY = new SegmentTree(1000001); +vector> X[1000001]; +vector> Y[1000001]; + +int main() { + cin.tie(0)->sync_with_stdio(0); + + cin >> N; + for (int i = 0, x, y, v; i < N; i++) { + cin >> x >> y >> v; + X[x].emplace_back(y, v); + Y[y].emplace_back(x, v); + segX->upt(0, 1000000, x, v, 1); + segY->upt(0, 1000000, y, v, 1); + } + + int ans = 0; + int xmx1 = 0, xmx2 = 0, xmx3 = 0; + for (int x = 0; x <= 1000000; x++) { + int sum = 0; + for (auto [y, v] : X[x]) { + segY->upt(0, 1000000, y, -v, 1); + sum += v; + } + auto [a, b] = segY->tree[1]; + ans = max(ans, sum + a + b); + for (auto [y, v] : X[x]) { + segY->upt(0, 1000000, y, v, 1); + } + if (sum > xmx1) xmx3 = xmx2, xmx2 = xmx1, xmx1 = sum; + else if (sum > xmx2) xmx3 = xmx2, xmx2 = sum; + else if (sum > xmx3) xmx3 = sum; + } + ans = max(ans, xmx1 + xmx2 + xmx3); + + int ymx1 = 0, ymx2 = 0, ymx3 = 0; + for (int y = 0; y <= 1000000; y++) { + int sum = 0; + for (auto [x, v] : Y[y]) { + segX->upt(0, 1000000, x, -v, 1); + sum += v; + } + auto [a, b] = segX->tree[1]; + ans = max(ans, sum + a + b); + for (auto [x, v] : Y[y]) { + segX->upt(0, 1000000, x, v, 1); + } + if (sum > ymx1) ymx3 = ymx2, ymx2 = ymx1, ymx1 = sum; + else if (sum > ymx2) ymx3 = ymx2, ymx2 = sum; + else if (sum > ymx3) ymx3 = sum; + } + ans = max(ans, ymx1 + ymx2 + ymx3); + + cout << ans; + +} +```