1 files changed, 50 insertions, 0 deletions
diff --git a/2020/January/Gold/boards.cpp b/2020/January/Gold/boards.cpp
new file mode 100644
index 0000000..812c959
--- /dev/null
+++ b/2020/January/Gold/boards.cpp
@@ -0,0 +1,50 @@
+#include <bits/stdc++.h>
+#define f first
+#define s second
+using namespace std;
+typedef pair<int, int> ii;
+constexpr int INF = 1e9;
+
+struct node {
+	int val; node* c[2];
+	node() { val = -INF; c[0] = c[1] = 0; }
+	node* get_c(int i) { return (!c[i] ? c[i] = new node : c[i]); }
+	void update(int x, int v, int l = 0, int r = INF) {
+		if (l == r) val = max(v, val);
+		else {
+			int m = (l + r) >> 1;
+			x <= m ? get_c(0)->update(x, v, l, m) : get_c(1)->update(x, v, m + 1, r);
+			val = max(c[0] ? c[0]->val : -INF, c[1] ? c[1]->val : -INF);
+		}
+	}
+	int query(int a, int b, int l = 0, int r = INF) {
+		if (a > r || b < l) return -INF;
+		if (a <= l && b >= r) return val;
+		int m = (l + r) >> 1;
+		return max(c[0] ? c[0]->query(a, b, l, m) : -INF, c[1] ? c[1]->query(a, b, m + 1, r) : -INF);
+	}
+} seg;
+
+pair<ii, ii> A[100001];
+
+int main() {
+	ifstream cin("boards.in");
+	ofstream cout("boards.out");
+
+	int N, P;
+	cin >> N >> P;
+	for (int i = 0; i < P; ++i) cin >> A[i].f.f >> A[i].f.s >> A[i].s.f >> A[i].s.s;
+	sort(A, A + P);
+	
+	seg.update(0, 0);
+	set<pair<ii, int>> S;
+	for (int i = 0; i < P; ++i) {
+		S.emplace(A[i].s, A[i].f.f + A[i].f.s - seg.query(0, A[i].f.s));
+		auto it = S.begin();
+		while (it != S.end() && it->f.f <= (i < P - 1 ? A[i + 1].f.f : INF)) {
+			seg.update(it->f.s, it->f.f + it->f.s - it->s);
+			it = S.erase(it);
+		}		
+	}
+	cout << 2 * N - seg.query(0, N);
+}